Pathology Case Studies (Chapter 7-9) WebPath

A 66-year-old man with Parkinson disease develops pleuritic chest pain. On exam, he has guarding over the right lower lung with dullness to percussion. A chest CT scan shows a focal, wedge-shaped pleural baesed area of hemorrhage in the right lower lobe. Which of the following is the most likely cause for his pulmonary lesion? A Embolism B Atherosclerosis C Vasculitis D Arteriolosclerosis E Thrombosis

(A) A pulmonary infarction is described. A thromboembolus from the venous circulation, usually arising in large leg veins, has lodged in a peripheral pulmonary arterial branch. The bronchial arterial supply to the lung does not provide enough oxygenation to prevent infarction, but does provide blood to make the infarct hemorrhagic. His neurodegenerative disorder with reduced movement is a risk for phlebothrombosis.

Question 43 A 3 month old male infant was born at term with no congenital anomalies noted. His mother has noted marked abdominal enlargement along with infrequent bowel movements for the past week. On physical examination his abdomen is distended but there does not appear to be appreciable tenderness. A plain film abdominal radiograph reveals marked colonic dilation. What pathologic finding is most likely to be present in this infant? A Aganglionic colonic segment B Congenital bowel malrotation C Cecal volvulus D Ileal intussusception E Meconium ileus F Rhabdomyosarcoma

(A) CORRECT. A megacolon at this age is typical for Hirschsprung disease in which the submucosal and myenteric plexuses lack ganglion cells.

Question 13 A 72-year-old woman notes increasing jaundice and nausea for the past month. On physical examination she is afebrile, but scleral icterus is present. There is no abdominal pain on palpation. She has active bowel sounds. A stool sample tested for occult blood is negative. Laboratory findings include total protein 6.1 g/dL, albumin 3.3 g/dL, alkaline phosphatase 210 U/L, AST 49 U/L, ALT 40 U/L, total bilirubin 7.2 mg/dL, and direct bilirubin 6.3 mg/dL. Her serum lipase is 50 U/L. Which of the following conditions is she most likely to have? A Pancreatic adenocarcinoma B Cystic fibrosis C Chronic active hepatitis D Primary biliary cirrhosis E Chronic persistent hepatitis F Autoimmune hemolytic anemia

(A) CORRECT. Adenocarcinoma of the head of pancreas produces extrahepatic biliary obstruction with an elevation predominantly of the direct bilirubin along with an elevation in alkaline phosphatase. This results in the classic finding of 'painless jaundice'.

Question 6 A 15-year-old boy from Ghana has the acute onset of right upper quadrant abdominal pain. Abdominal ultrasound reveals a dilated gallbladder with thickened wall and filled with calculi. A laparoscopic cholecystectomy is performed. The pathologist assistant opens the gallbladder to reveal ten multifaceted 0.5 to 1 cm diameter dark, greenish-black gallstones. Which of the following underlying conditions does this boy most likely have? A Sickle cell anemia B Crohn disease C Hypercholesterolemia D Hyperparathyroidism E Primary biliary cirrhosis F Schistosomiasis

(A) CORRECT. Darkly pigmented gallstones usually contain bilirubin. Hyperbilirubinemia is a consequence of hemolysis. Patients with sickle cell anemia have chronic hemolysis.

A 42-year-old man has been an intravenous drug user of heroin for 20 years. He has noted blood-streaked stool on defecation for the past week. On physical examination there are needle tracks in his left antecubital fossa. He is afebrile. Which of the following is the most likely diagnosis? A Hemorrhoids B Megacolon C Angiodysplasia D Perirectal fistulae E Adenocarcinoma

(A) CORRECT. Hemorrhoids form in the setting of chronic constipation. (Actually, this is probably the worst direct consequence of opiate usage; most of the serious health problems arise from nonsterile injection of the drug with risk for infections such as hepatitis and HIV, as well as bacterial sepsis). Hemorrhoids are quite common in the population as a whole and become more frequent with aging.

A 25-year-old previously healthy woman collapses suddenly and unexpectedly. Echocardiography shows global hypokinesis with increased left ventricular end diastolic and systolic size, along with systolic left ventricular dysfunctionwith decreased ejection fraction. An endomyocardial biopsy is obtained and microscopically, the myocardium shows infiltration by small lymphocytes, with focal myocyte necrosis. Which of the following infectious agents is most likely to have caused these findings? A Coxsackie B virus B Candida albicans C Aspergillus fumigatus D Streptococcus, viridans group E Staphylococcus aureus F Cytomegalovirus G Streptococcus, group A

(A) CORRECT. The most common cause for a primary myocarditis is a virus (such as Coxsackie virus). The myocardial fiber necrosis with lymphocytic infiltrates are consistent with viral infection. Viral myocarditis can be a cause for sudden death in a young person.

A 66-year-old man has had increasing malaise for the past year. On physical examination auscultation of the chest reveals a friction rub. Laboratory studies show a serum urea nitrogen of 100 mg/dL and creatinine of 9.8 mg/dL. Which of the following forms of pericarditis is he most likely to have? A Fibrinous B Hemorrhagic C Purulent D Serous E Constrictive

(A) CORRECT. The uremia leads to exudation of fibrin onto the epicardial and pericardial surfaces. There is often accompanying fluid, and the term serofibrinous exudate may be used.

Question 18 A 41-year-old man has experienced progressive fatigue, pruritus, and icterus for the past 4 months. He had a total colectomy performed five years ago. On physical examination he is afebrile. Scleral icterus is present. His stool from a Koch pouch is negative for occult blood. Cholangiography reveals the widespread obliteration of intrahepatic bile ducts. A liver biopsy is performed and on microscopic examination shows periductular "onion skin" fibrosis with a moderate lymphocytic infiltrate. Some intrahepatic bile ducts are obliterated, but there is no piecemeal necrosis. Which of the following underlying diseases is he most likely to have? A Ulcerative colitis B Systemic lupus erythematosus C Wilson disease D Hepatitis B viral infection E Primary biliary cirrhosis F Alpha-1-antitrypsin deficiency

(A) CORRECT. Sclerosing cholangitis is one of the extra-intestinal manifestations of inflammatory bowel disease and is seen most frequently with ulcerative colitis. The colectomy was probably performed because of his increasing risk for adenocarcinoma, but even after colectomy extraintestinal manifestations of UC can occur.

Question 25 A 53-year-old postmenopausal woman has been feeling increasingly tired for 3 months. She has had mid-epigastric pain for the past month. On physical examination her stool is positive for occult blood. Laboratory findings include a WBC count of 6300/uL, Hgb 12.0 g/dL, Hct 35.4%, MCV 73 fL, platelet count 236,000/uL, total protein 6.0 g/dL, albumin 3.5 g/dL, alkaline phosphatase 270 U/L, AST 84 U/L, ALT 35 U/L, lipase 45 U/L, total bilirubin 1.1 mg/dL, and direct bilirubin 0.8 mg/dL. Which of the following is the most likely explanation for her findings? A Hepatic metastases B Wilson disease C Acute hepatitis A D Acetaminophen toxicity E Congestive heart failure F Chronic alcohol abuse G Non-alcoholic fatty liver

(A) CORRECT. The elevation in the alkaline phosphatase in the absence of an elevated bilirubin suggests focal hepatic obstruction, which could occur with metastases. The positive stool guaiac suggests a colonic primary.

Question 5 A 38-year-old man has had upper abdominal pain for 3 months. For the past week he has had nausea. On physical examination a stool sample tested for occult blood is positive. An upper GI endoscopy reveals no esophageal lesions, but there is a solitary 2 cm diameter shallow, sharply demarcated ulceration of the stomach. Which of the following is most characteristic for this lesion? A Antral location B Potential for metastases C Increased gastric acid production. D No need for biopsy E Accompanying pancreatic gastrinoma

(A) CORRECT. The gastric antrum is the typical location for a benign peptic ulcer.

A 70-year-old healthy woman has a check of her health status. On examination her blood pressure is 125/80 mm Hg and BMI 24 kg/m2. Laboratory studies show her serum total cholesterol is 180 mg/dL with LDL cholesterol 90 mg/dL. There is a family history of cancer. Which of the following is a constitutional risk factor for atherosclerotic vascular disease in this woman? A Age B Blood pressure C Family history D Gender E Hyperlipidemia F Weight

(A) Her age is a risk factor for atherosclerosis. However, a healthy lifestyle can negate this risk. Many older persons are not pursuing a healthy lifestyle.

A 74-year-old man has had increasingly severe headaches for 2 months, centered on the right. His vital signs include T 36.9°C, P 82/minute, RR 14/minute, and BP 130/85 mm Hg. There is a palpable tender cord-like area over his right temple. His heart rate is regular with no murmurs, gallops, or rubs. Pulses are equal and full in all extremities. A biopsy of this lesion is obtained, and microscopic examination reveals a muscular artery with luminal narrowing and medial inflammation with lymphocytes, macrophages, and occasional giant cells. He improves with a course of high-dose corticosteroid therapy. Which of the following laboratory test findings is most likely to be present with this man's disease? A Erythrocyte sedimentation rate of 110 mm/hr B Rheumatoid factor titer of 80 IU/mL C HDL cholesterol of 15 mg/dL D Anti-double stranded DNA titer of 1:1024 E pANCA titer of 1:160

(A) CORRECT. These are classic findings for temporal arteritis, the most typical involvement with giant cell arteritis. Corticosteroid therapy typically produces a diminution in the symptoms. Biopsy of the artery can remove the offending site of inflammation and relieve symptoms (don't worry--there are collateral branches). Not treating this condition puts the patient at risk for involvement of other branches of the external carotid artery, the worst of which would be the ophthalmic branch. The elevation of the sed rate is way out of proportion to the extent and amount of inflammation in this one arterial segment.

A 25-year-old man dies suddenly and unexpectedly while at a nightclub late one evening. The medical examiner performs an autopsy. There is no evidence for trauma on external examination of the body. There are no gross pathologic findings of internal organs. Postmortem toxicologic findings are significant for high blood levels of cocaine and its metabolite benzoylecgonine. Which of the following is the most likely histopathologic finding involving his heart? A Contraction band necrosis B Lymphocytic myocarditis C Myofiber disarray D Coronary thrombosis E Pericardial tamponade

(A) CORRECT. This finding has been associated with sudden death and cocaine use. It is thought that it may be mediated by high norepinephrine levels through blockage of catecholamine reuptake. Continued use may promote arteriopathy in small peripheral coronary branches.

A 35-year-old man was found down, was delirious, and talking incoherently. On examination in the emergency department his temperature is 39.3°C, pulse 110/minute, and blood pressure 70/palpable. He has a heart murmur, palpable spleen tip, and splinter hemorrhages of fingernails. Which of the following laboratory findings is most likely to be present in this man? A Positive urine screen for opiates B Elevated anti-streptolysin O (ASO) C Increased urinary free catecholamines D Elevated Coxsackie B viral titer E Rising creatine kinase (CK) in serum

(A) CORRECT. This history points to an infective endocarditis. A common risk factor for infective endocarditis, particularly with more severe and acute disease, is intravenous drug use.

Question 28 A 51-year-old man undergoes routine health examination by his nurse practitioner. There are no abnormal physical examination findings except for a stool sample positive for occult blood. Colonoscopy is performed and there is a 1 cm polyp on a narrow stalk located in the descending colon at 30 cm from the anal verge. The polyp is resected and on microscopic examination shows crowded, tubular, atypical colonic-type glands. The stalk of the polyp is covered with normal colonic epithelium. Which of the following is the most likely diagnosis? A Adenomatous polyp B Inflammatory fibroid polyp C Peutz-Jeghers polyp D Ulcerative colitis pseudopolyp E Hyperplastic polyp F Crohn disease

(A) CORRECT. This is the typical appearance for a tubular adenoma, also called an adenomatous polyp. Small ones are likely to be benign, and they can easily be removed. This is the value of screening.

A 57-year-old man has had blood pressure measurements in the range of 160/95 to 180/110 mm Hg for many years. He has taken no medications. A renal scan reveals kidneys of normal size for age. These findings with benign nephrosclerosis are most likely to occur with which of the following vascular changes? A Hyaline arteriolosclerosis B Monckeberg's medial calcific sclerosis C Complex calcified atherosclerosis D Arterial mural thrombosis E Hyperplastic arteriolosclerosis

(A) Hyaline arteriolosclerosis is a feature of long-standing hypertension and is part of benign nephrosclerosis which may go on for many years with no complications. The small arterioles are thickened with pink (hyaline) proteinaceous deposits.

A 44-year-old African-American man has had elevated blood pressure for years which has not been treated. He now has severe headaches. On physical examination his blood pressure is 275/150 mm Hg. Laboratory studies show Hgb 13.8 g/dL, serum glucose 76 mg/dL, and creatinine 3.5 mg/dL. These findings are most likely to be associated with which of the following pathologic lesions involving his kidneys? A Hyperplastic arteriolosclerosis B Hyaline arteriolosclerosis C Monckeberg medial calcific sclerosis D Atherosclerosis E Thrombophlebitis

(A) Hyperplastic arteriolosclerosis is seen in the setting of malignant hypertension, and renal failure is common.

A 58-year-old woman has the sudden onset of severe dyspnea with chest pain and diaphoresis. A chest CT scan shows areas of decreased attenuation within the main pulmonary arteries. Her D-dimer assay is elevated. Her acute event is most likely to be a consequence of which of the following? A Placement of a hip prosthesis B Marked thrombocytopenia C Chronic alcoholism D Infection with the human immunodeficiency virus E Rheumatoid arthritis

(A) Immobilization is a major risk for the development of venous thrombosis and subsequent pulmonary embolization (the areas of diminished attenuation). Immobilization occurs following surgery. The postoperative goal: get the patient mobile as soon as possible, and meanwhile employ methods to reduce the risk for thrombosis.

n an experiment, a glass bead is embolized to a branch of the renal artery. A day later there is a focal area in which the renal parenchymal cells in the distribution of the occluded artery show karyolysis and karyorrhexis. The outlines of the cells are still visible, but the nuclei have lost basophilic staining and the cytoplasm is eosinophilic but pale. Which of the following types of cellular necrosis is most likely present? A Caseous B Coagulative C Fatty D Gangrenous E Liquefactive

(B) A typical ischemic infarction with coagulative necrosis is described. Coagulative necrosis is most likely to occur in solid internal organs with high metabolic demands.

A 54-year-old man with diabetes mellitus has had 3 urinary tract infections during the past year. He now sees the physician for an ulceration on his right big toe which has not healed in 2 months. Laboratory studies on each of his doctor visits over the past year show blood glucose levels below 110 mg/dL. This situation could be best explained by which of the following laboratory findings? A Elevated hemoglobin A1C level B Increased urine ketones C Elevated serum osmolarity D Decreased plasma insulin E Elevated titer of anti-insulin antibodies

(A) Out-of-control diabetes over time can be better detected because the glycosylated RBCs will persist for months and the Hgb A1C increased. Single glucose values reflect the past few hours. His problems developed over years.

A 57-year-old woman has had episodes of abdominal pain following meals for the past year. Her BMI is 31. She has hypertension. Her total serum cholesterol is increased. Which of the following types of blood vessel is the most likely location for the pathologic abnormality causing her pain? A Artery B Arteriole C Capillary D Venule E Vein

(A) She has abdominal angina from vascular insufficiency. She has multiple risk factors for atherosclerosis. Atherosclerosis occurs in muscular arteries, because the level of blood pressure in arteries predisposes to endothelial dysfunction.

A 63-year-old man has had increasing exercise intolerance for the past 6 years so that he now becomes short of breath upon climbing a single flight of stairs. Laboratory studies have shown fasting blood glucose measurements from 145 to 210 mg/dL for the past 25 years, but he has not sought medical treatment. If he dies suddenly, which of the following is most likely to be the immediate cause of death? A Myocardial infarction B Nodular glomerulosclerosis C Cerebral hemorrhage D Hyperosmolar coma E Right lower leg gangrene

(A) This is the most common cause of death in persons with diabetes mellitus, because of the high prevalence of advanced coronary atherosclerosis.

An autopsy study reveals that evidence for atheroma formation can begin even in children. The gross appearances of the aortas are recorded and compared with microscopic findings of atheroma formation. Which of the following is most likely to be the first visible gross evidence for the formation of an atheroma? A Thrombus B Fatty streak C Calcification D Hemorrhage E Exudate F Ulceration

(B) A fatty streak on the arterial intimal surface is the first grossly visible sign of atheroma formation. It is benign and reversible, but it may be the precursor to more severe plaques.

A study of atherogenesis is performed. There is a propensity for atheromas to form at muscular arterial branch points, such as the carotid and aortic bifurcations. Which of the following events in the arteries at these locations is most likely to initiate atherogenesis? A Collagen synthesis B Endothelial dysfunction C Lactic acidosis D Cholesterol breakdown E Hypoxemia

(B) A variety of stressors may affect endothelial cells, including the shear stress from turbulent flow at arterial branch points. Endothelial dysfunction is the initiating event that allows insudation of lipids to promote atherogenesis.

A 71-year-old woman experiences a transient ischemic attack (TiA). She had an acute myocardial infarction 5 years ago. Which of the following physical examination findings is most likely to be associated with her TIA? A Blood pressure 140/90 mm Hg B Carotid bruit C Heart rate of 100/minute D Leg swelling E Pulsatile abdominal mass F Radial pulse 1+

(B) Atheromatous plaques tend to form initially where there is vascular turbulence, and a bruit is indicative of arterial narrowing at the carotid bifurcation. The turbulence drives endothelial injury that contributes to atheroma formation.

A 49-year-old man has the sudden onset of substernal chest pain with radiation to his left arm. This persists for the next 6 hours. He goes to the emergency department and on examination is afebrile. Laboratory studies show a serum troponin I of 18 ng/mL. Angiography reveals a thrombosis of the anterior interventricular (left anterior descending) coronary artery. During the next 24 hours, which of the following is the most likely complication he will experience? A Constrictive pericarditis B Arrhythmia C Hepatic necrosis D Thromboembolism E Cardiac tamponade

(B) CORRECT. A primary reason for putting a patient with an acute myocardial infarction in hospital is to prevent arrhythmias.

Question 35 A 38-year-old woman has experienced episodes of light-headedness, irritability, and difficulty concentrating at her work for the past year. On physical examination there are no abnormal findings. Laboratory studies show her hemoglobin is 14.2 g/dL. An abdominal CT scan shows a 1 cm mass in the tail of the pancreas. Which of the following is the most likely diagnosis? A Carcinoid tumor B Insulinoma C Adenocarcinoma D Pseudocyst E Pheochromocytoma F Neuroendocrine carcinoma

(B) CORRECT. A variety of hormones can potentially be elaborated by islet cell adenomas, but the most common is insulin, leading to hypoglycemia. This hypoglycemia may occur periodically. Often, the adenoma is so small that it is difficult to detect by radiologic imaging techniques.

A 66-year-old man has had congestive heart failure with increasing pulmonary congestion and edema for the past year. He had been previously healthy all his life with no major illnesses. On physical examination his blood pressure is 125/85 mm Hg and he is afebrile. A systolic ejection click is auscultated. A chest x-ray shows cardiomegaly with a prominent left heart border and pulmonary edema. Laboratory studies show a serum glucose of 95 mg/dL and total serum cholesterol of 175 mg/dL. His serum creatine kinase is not elevated. Which of the following underlying diseases is he most likely to have? A Alcoholic cardiomyopathy B Calcified bicuspid aortic valve C Tricuspid valve endocarditis D Aortic dissection E Cardiac amyloidosis

(B) CORRECT. Although bicuspid aortic valves are present from birth, they do not manifest with significant calcification and stenosis until later adult life. The presence of pulmonary edema but lack of peripheral edema points to a left-sided cause for his congestive failure. He does not have systemic hypertension.

A 51-year-old man has the sudden onset of substernal chest pain which radiates to his left arm and neck. He becomes light-headed and diaphoretic over the next 3 hours. He goes to the emergency room. On examination he is afebrile but has a heart rate of 96/minute with an irregular rhythm. Laboratory studies show an increased serum troponin I. Which of the following features would be most prominent by histopathologic examination of his myocardium at this point in time? A Macrophage infiltration B Contraction band necrosis C Neutrophilic infiltration D Capillary proliferation E Collagen deposition

(B) CORRECT. Contraction band necrosis is an initial change as the myocardial fibers begin to die within the first day of onset of myocardial infarction. Neutrophils become more numerous following the first day.

Question 31 A 54-year-old man has complained for 5 months of upper abdominal pain accompanied by nausea. He does not have hematemesis. On physical examination the only finding is a stool sample positive for occult blood. Upper GI endoscopy is performed and gastric biopsies are taken that on microscopic examination reveal acute and chronic mucosal inflammation along with the presence of Helicobacter pylori organisms. The presence of these organisms is most likely to be associated with which of the following? A Gastric mucosal invasion with septicemia B Duodenal peptic ulceration C Pernicious anemia D Hypochlorhydria E Diffuse large B cell lymphoma

(B) CORRECT. H. pylori is present in about 90% of cases of chronic gastritis and nearly 100% of cases of duodenal ulceration. H. pylori is present with increasing frequency with age, which suggests that it is an important cause for chronic gastritis in the elderly.

Question 26 A 25-year-old man complains of a low volume but chronic, foul smelling diarrhea for the past year. He has no nausea or vomiting. On physical examination there is no abdominal pain or masses and bowel sounds are present. His stool is negative for occult blood. Laboratory studies include a quantitative stool fat of 10 g/day. Upper GI endoscopy is performed with biopsies taken of the duodenum, and on microscopic examination show absence of villi, increased surface intraepithelial lymphocytes, and hyperplastic appearing crypts. Which of the following therapies is most likely to be useful for this man? A Antibiotics B Gluten-free diet C Selective vagotomy D Corticosteroids E Segmental duodenal resection F Aromatherapy

(B) CORRECT. He has celiac disease from ingestion of grains (wheat, rye, barley) that contain gluten with gliaden protein. The enzyme tissue transglutamidase breaks down the gliaden into peptides which, when displayed to antigen presenting cells, activate CD4 lymphocytes that produce the mucosal inflammation.

A clinical study is performed to document complications in persons with glomerulonephritis and with laboratory studies showing an elevated antinuclear antibody and anti-ds-DNA titer. Which of the following cardiac abnormalities is most likely to be present? A Pancarditis B Libman-Sacks endocarditis C Hemorrhagic pericarditis D Lipofuscin deposition E Coronary artery vasculitis

(B) CORRECT. Libman-Sacks endocarditis is most often seen in patients with autoimmune diseases such as systemic lupus erythematosus, and SLE often has renal complications with glomerulonephritis.

Question 24 A 45-year-old woman has noted difficulty swallowing for the past 6 months. On physical examination there are no abnormal findings. A barium swallow reveals an area of stricture in the lower esophagus just above the gastroesophageal junction. She has an upper GI endoscopy performed and biopsies of the lower esophagus are taken which show squamous epithelium with no acute or chronic inflammation or ulceration, only submucosal atrophy along with fibrosis of smooth muscle. Which of the following is the most likely diagnosis? A Mallory-Weiss syndrome B CREST syndrome C Iron deficiency D Portal hypertension E Barrett esophagus

(B) CORRECT. Patients with progressive systemic sclerosis with either the limited form of the disease (sometimes called CREST syndrome) or diffuse scleroderma have fibrosis in the gastrointestinal tract, most often involving the esophagus. An endoscopic procedure to dilate the esophagus may need to be performed periodically.

A 51-year-old woman has had several syncopal episodes over the past year. Each episode is characterized by sudden but brief loss of consciousness. She reports no chest pain. On physical examination her vital signs show T 36.9°C, P 80/minute, RR 16/minute, and BP 110/75 mm Hg. She has no pedal edema. On brain MR imaging there is a 1.5 cm cystic area in the left parietal cortex. A chest radiograph shows no cardiac enlargement, and her lung fields are normal. Her serum total cholesterol is 165 mg/dL. Which of the following cardiac lesions is she most likely to have? A Cardiac amyloidosis B Left atrial myxoma C Tuberculous pericarditis D Mitral valve prolapse E Ischemic cardiomyopathy

(B) CORRECT. Primary cardiac neoplasms are uncommon. Of these, the most common is myxoma. Atrial myxomas are more often on the left. Though benign, they can occlude the mitral valve and produce sudden loss of cardiac output. They may embolize small portions of themselves or thrombus formed over their surface.

A 17-year-old girl is short in stature for her age. She has not yet shown any changes of puberty. On physical examination her vital signs include T 37°C, RR 18/minute, P 75/minute, and BP 165/85 mm Hg. She has a continuous murmur heard over both the front of the chest as well as her back. Her lower extremities are cool with diminished pulses and poor capillary filling. She has a webbed neck. A chest radiograph reveals a prominent left heart border, no edema or effusions, and rib notching. Which of the following cardiovascular abnormalities is she most likely to have? A Shortening and thickening of chordae tendineae of the mitral valve B Narrowing of the aorta past the ductus arteriosus C Supravalvular narrowing in the aortic root D Lack of development of the spiral septum and partial absence of conus musculature E Single large atrioventricular valve

(B) CORRECT. She has coarctation of the aorta, and the constriction is postductal, allowing prolonged survival. Blood pressure is elevated in the upper body but reduced in the lower body. Her physical characteristics also suggest Turner syndrome (monosomy X).

A 69-year-old woman with a 7 kg weight loss over the past 6 months now has developed painless jaundice over the past 2 weeks. On physical examination she is afebrile. An abdominal CT scan shows a large mass involving the head of the pancreas, along with widespread nodules in the liver. Nodules are seen in both lungs by chest radiograph. Which of the following cardiac abnormalities is she most likely to develop? A Dilated cardiomyopathy B Non-bacterial thrombotic endocarditis C Acute fibrinous pericarditis D Endocardial fibrosis E Acute myocardial infarction

(B) CORRECT. Such pancreatic cancers can produce paraneoplastic syndromes and be associated with a hypercoagulable state (Trousseau's syndrome) with formation of marantic cardiac valvular vegetations.

A 22-year-old man has had increasing malaise over the past 3 weeks. On physical examination his vital signs show T 39.2°C, P 105/minute, RR 30/minute, and BP 80/40 mm Hg. On auscultation of his chest a loud systolic cardiac murmur is heard, and his lungs have bibasilar crackles. Needle tracks are seen in his left antecubital fossa. He has splinter hemorrhages noted on fingernails, as well as painful erythematous nodules on palmar surfaces. A tender spleen tip is palpable. A chest radiograph shows pronounced pulmonary edema. Which of the following laboratory test findings is most likely to be present in this patient's peripheral blood? A Creatine kinase-MB of 8% with a total CK 389 U/L B Positive blood culture for Pseudomonas aeruginosa C Total serum cholesterol of 374 mg/dL D Blood urea nitrogen of 118 mg/dL E Antinuclear antibody titer of 1:512

(B) CORRECT. The history points to infectious endocarditis and acute congestive heart failure. Staphylococcus aureus and Pseudomonas aeruginosa are the most likely organisms to be found with a history of injection drug use.

A 65-year-old man has sudden onset of severe abdominal pain that has persisted for 3 hours. Physical examination reveals his temperature is 37°C, heart rate 110/minute, respirations 25/minute, and blood pressure 145/100 mmHg. He has diminished pulses in the lower extremities. There is a pulsatile abdominal mass. His serum creatine kinase is not elevated. He has had fasting blood glucose measurements in the range of 140 to 180 mg/dL for over 20 years. Which of the following conditions is he most likely to have? A Superior mesenteric artery thrombosis B Atherosclerotic aortic aneurysm C Polyarteritis nodosa D Acute coronary syndrome E Monckeberg's medial calcific sclerosis

(B) CORRECT. The infrarenal portion of the abdominal aorta typically involved with an atherosclerotic aneurysm is markedly enlarged and filled with thrombus. Risk for rupture increases with size of the aneurysm. Risk factors for atherosclerosis here include both diabetes mellitus and hypertension.

Question 1 A 41-year-old man has a history of drinking 1 to 2 liters of whisky per day for the past 20 years. He has had numerous episodes of nausea and vomiting in the past 5 years. He now experiences a bout of prolonged vomiting, followed by massive hematemesis. On physical examination his vital signs are T 36.9 C, P 110/min, RR 22/min, and BP 80/40 mm Hg lying down. His heart has a regular rate and rhythm with no murmurs and his lungs are clear to auscultation. There is no abdominal tenderness or distension and bowel sounds are present. His stool is negative for occult blood. Which of the following is the most likely diagnosis? A Hiatal hernia B Esophageal laceration (Mallory-Weiss syndrome) C Esophageal pulsion diverticulum D Barrett esophagus E Esophageal squamous cell carcinoma F Esophageal stricture

(B) CORRECT. The lacerations are induced by the forceful, prolonged vomiting and can extend to submucosal veins that bleed profusely. Esophageal variceal bleeding should also be suspected with such a history. The acute nature of the process means no blood has yet passed through the bowel to the rectum.

A 23-year-old primigravida gives birth following an uncomplicated pregnancy to a 2870 gm girl infant. The baby initially does well, but 12 hours following delivery she develops respiratory difficulty. On examination the infant has a poor color, weak pulses, and oxygen saturation of only 90%. Which of the following cardiac findings is this infant most likely to have? A Muscular ventricular septal defect B Hypoplastic left heart C Complete transposition with no shunt D Secundum type atrial septal defect E Congenital Group B Streptococcus infection

(B) CORRECT. The poor outcome so soon after birth suggests a severe defect, and lack of sufficient left heart to provide appropriate cardiac output can explain these findings. There can be varying degrees of hypoplasia which determine how long the child survives.

A 56-year-old man has a routine checkup. He is found to have a blood pressure of 175/110 mm Hg. A month later his blood pressure is 170/105 mm Hg. He elects to do nothing about this, because he feels fine. If he remains untreated, this man is at greatest risk for which of the following conditions? A Pleural effusions B Pulmonary congestion C Hyperplastic arteriolosclerosis D Tricuspid insufficiency E Myocardial infarction

(B) CORRECT. The pressure load on the left ventricle will always lead to left venricular hypertrophy, and if untreated eventually the heart can no longer compensate and there is left heart failure, which leads to pulmonary congestion and edema.

Question 2 A 50-year-old man has had persistent nausea for 5 years with occasional vomiting. On physical examination there are no abnormal findings. He undergoes an upper GI endoscopy, and a small area of gastric fundal mucosa has loss of rugal folds. Biopsies are taken and microscopically reveal well-differentiated adenocarcinoma confined to the mucosa. An upper GI endoscopy performed 5 years previously showed a pattern of gastritis and microscopically there was chronic inflammation with the presence of Helicobacter pylori. Which of the following interpretations is most applicable to his neoplasm? A Metastases limited to regional lymph nodes B A 5-year survival following resection of >90% C A signet ring cell pattern by light microscopy D The gross appearance of linitis plastica E A high prevalence in the United States

(B) CORRECT. The prognosis with early gastric carcinoma (EGC) is good, compared with other gastric cancers.

An epidemiologic study of eating habits is performed. Dietary patterns of adult patients are recorded and compared to risk for cardiovascular diseases. It is observed that persons who eat bacon for breakfast are more likely to have cardiovascular disease than persons who eat oat bran cereal. Which of the following conditions is the 'bacon' group most likely to have? A Mitral annulus calcification B Ventricular aneurysm C Left atrial dilation D Thoracic aortic aneurysm E Aortic valve stenosis

(B) CORRECT. The ventricular aneurysm is a complication of myocardial infarction. The incidence of MI is increased with an atherogenic diet.

A 27-year-old man has become severely ill with fever and malaise over the past 3 days following tooth extraction. On examination he has a temperature of 38.8°C, heart rate of 105/minute, respiratory rate of 24/min, and blood pressure of 80/40 mm Hg. He has a widely split S2 heart sound and a rumbling mid-diastolic murmur. He has small hemorrhages visible on nail beds. His spleen tip is palpable. Which of the following cardiac conditions is most likely to predispose him to this acute illness? A Hypoplastic left heart syndrome B Atrial septal defect C Chagas disease D Coronary atherosclerosis E Hypertrophic cardiomyopathy

(B) CORRECT. This congenital condition can predispose to infective endocarditis. If such conditions are known, then antibiotic prophylaxis can be given prior to invasive or dental procedures that increase the risk for bacteremia.

A 63-year-old woman has the sudden onset of 'knife-like' pain in the chest radiating to the back. She has been previously healthy except for a history of poorly controlled hypertension. She is transported to the hospital and on arrival she has a heart rate of 90/minute, respirations 20/minute, temperature 36.8°C, and blood pressure 150/100 mm Hg. No murmurs, rubs, or gallops are audible. A chest radiograph reveals a widened mediastinum. Laboratory findings include a total serum creatine kinase of 55 U/L, creatinine 0.9 mg/dL, and glucose 123 mg/dL. Which of the following is the most likely diagnosis? A Fibrinous pericarditis B Aortic dissection C Infective endocarditis D Dilated cardiomyopathy E Myocardial infarction

(B) CORRECT. This is a classic history for an aortic dissection. A tear in the aortic intima is followed by dissection of blood outward, into the medial layer, and then through the adventitia, often into the thoracic cavity, with fatal hemothorax. The risk factors in most adults include atherosclerosis and hypertension. In Marfan syndrome, the risk for aortic dilation and dissection results from cystic medial necrosis, but this occurs at a much younger age.

Question 22 A 28-year-old woman with recent onset of a major depressive disorder ingests an entire bottle (100 capsules, 500 mg each) of a medication containing acetaminophen. She becomes progressively obtunded over the next 8 hours. Which of the following microscopic findings is most likely to be present in her liver 3 days following this ingestion? A Normal histology B Extensive necrosis C Bridging fibrosis D Severe steatosis E Portal chronic inflammation F Intracanalicular cholestasis

(B) CORRECT. This is a massive overdose of acetaminophen, which causes extensive hepatic necrosis.

Question 16 A 44-year-old man, an emergency medical technician, has been feeling fatigued for the past 4 months. He remembers that he had experienced an episode of jaundice about 10 years ago, but that resolved and he has been healthy since. On physical examination there are no remarkable findings. Laboratory studies show his hemoglobin is 14.0 g/dL and serum electrolytes normal, but he has a total protein of 5.4 g/dL, albumin of 2.9 g/dL, ALT 132 U/L and AST 113 U/L with total bilirubin 1.3 mg/dL and direct bilirubin 0.8 mg/dL. A liver biopsy is performed and microscopic examination shows disruption of the limiting plate of hepatocytes with extension of inflammation into the lobules from the triads. There is focal ballooning degeneration of hepatocytes. Which of the following laboratory test findings is most characteristic for his disease? A Decreased serum alpha-1-antitrypsin B Positive hepatitis B surface antigen C Increased serum ferritin D Decreased serum ceruloplasmin E Positive antimitochondrial antibody

(B) CORRECT. This is chronic active hepatitis with hepatitis B infection. This illustrates the wisdom of getting the series of hepatitis B vaccinations.

Question 4 A 30-year-old man incurs a stab wound to the abdomen. He is taken to surgery and while repairing the small intestine, the surgeon notices the presence of a 1 cm circumscribed submucosal mass in the ileum. The lesion is resected and on gross examination has a firm, yellow-tan cut surface. Microscopically, the mass is composed of nests of cells with uniform small round nuclei and cytoplasm with small purple granules. The cytoplasm is positive with antibody to chromogranin on immunohistochemical staining. Which of the following pathologic findings is most likely to accompany this man's lesion? A Liver metastases B Another similar lesion C Multiple gastric ulcerations D Pancreatic adenocarcinoma E Inflammatory bowel disease F Tropheryma whippelii infection

(B) CORRECT. This lesion is a carcinoid tumor, and these neoplasms can be multiple. Small carcinoids typically act in a benign fashion. Most of them do not secrete hormones causing clinical symptoms, but some do. They are often incidental findings.

Following a meal, lipids are digested and absorbed. Lipids collect within enterocytes. Which of the following chemical components of the blood is mainly responsible for transporting exogenous (dietary) triglyceride from the intestine to the liver? A Apoprotein B Chylomicron C Lipoprotein lipase D Oxidized low density lipoprotein E High density lipoprotein

(B) Chylomicrons formed in intestinal epithelial cells contain apoproteins, triglyceride and cholesterol.

A 30-year-old man goes to his physician for a routine health checkup. On physical examination there are no abnormal findings. Laboratory test findings include serum glucose 80 mg/dL, hemoglobin A1C 4%, total cholesterol 240 mg/dL, LDL cholesterol 180 mg/dL, and HDL cholesterol 20 mg/dL. Through which of the following mechanisms is endothelial vascular injury in this patient most likely to occur? A Accumulation of sorbitol B Insudation of lipid C Inflammation with neutrophils D Deposition of immunoglobulins E Activation of complement

(B) He has hypercholesterolemia with more of the 'bad' LDL cholesterol that can become oxidized and taken up by modified arterial wall LDL receptors. The lipid collects in macrophages that transform to foam cells. These foam cells accumulate and becomes a lipid lesion--the precursor to more serious atheromatous plaques.

An autopsy study is conducted involving the gross appearance of the aorta of adults ranging in age from 60 to 90. In some of these patients, the aorta demonstrates atheromatous plaques covering from 70 to 95% of the intimal surface area, mainly in the abdominal portion, with ulceration and calcification. Which of the following contributing causes of death are these patients most likely to have? A Hyperparathyroidism B Hypertension C Marfan syndrome D Thrombophlebitis E Vasculitis F Colonic adenocarcinoma G Systemic lupus erythematosus

(B) Hypertension is a risk factor that accelerates atheromatous plaque formation.

A 73-year-old woman who exercises regularly falls down the stairs and injures her right hip. A radiograph is taken of the pelvis. There is no fracture but the radiograph reveals calcification of the small muscular arteries lateral to her uterus. What is the probable vascular lesion which accounts for this calcification? A Ulcerative atherosclerosis B Calcific medial sclerosis C Metastatic calcification D Trauma E Dystrophic calcification

(B) Monckeberg calcific medial sclerosis is a benign, incidental finding most often seen in the elderly. Small arteries in pelvis, breast, neck, and extremities are typically involved. The vascular lumen is not compromised.

62-year-old man has experienced substernal chest pain upon exertion with increasing frequency over the past 6 months. An electrocardiogram shows features consistent with ischemic heart disease. He has a total serum cholesterol of 262 mg/dL. By angiography, there is 75% narrowing of coronary arteries. In which of the following locations is a mural thrombus most likely to occur in this man? A Left atrium B Left ventricle C Right atrium D Right ventricle E Aorta F Vena cava

(B) The left ventricle is the major user of oxygen and nutrients and requires a good blood supply. A complication of ischemic heart disease with infarction is development of overlying mural thrombus. Such mural thrombi are likely to result from damage to the left ventricle from ischemic heart disease, either acutely with an underlying myocardial infarction, or with a left ventricular aneurysm formed following resolution of a large myocardial infarction

A 68-year-old woman has survived multiple episodes of pulmonary thromboembolism during the past three months. On physical examination there are no abnormal findings. Which of the following is the most likely underlying condition leading to this patient's recurrent pulmonary thromboembolism? A Micronodular cirrhosis of the liver B Adenocarcinoma of the pancreas C Thrombocytopenia D Familial hypercholesterolemia E Mitral valve endocarditis F Type II diabetes mellitus

(B) The recurrent episodes suggest a hypercoagulable state, and carcinomas can do this (Trousseau syndrome) by releasing substances that act as thromboplastins.

A 60-year-old woman has become increasingly obtunded over the past day. She was found by her daughter in a stuporous condition and brought to the emergency department. On physical examination, she has poor skin turgor. She is afebrile. Her vital signs reveal a blood pressure of 90/40 mm Hg, respirations 15 and shallow, pulse 95, and temperature 36°C. Laboratory studies show a hemoglobin A1C of 10%. Her serum electrolytes show sodium 144 mmol/L, potassium 5 mmol/L, chloride 95 mmol/L, CO2 22 mmol/L, and glucose 940 mg/dL. Which of the following is the most likely diagnosis? A Insulin overdose B Hyperosmolar coma C Hyperlipidemia D Ketoacidosis E Overeating

(B) This is an extremely elevated serum glucose that would increase the serum osmolality markedly.

A longitudinal study is conducted to detect serum markers that predict risk for death from acute coronary syndromes. A marker is identified that is synthesized and released from the liver in response to formation of cytokines in atheromatous plaques. This marker increases endothelial adhesiveness to platelets. What is this marker most likely to be? A Prostacyclin B Immunoglobulin G C C-reative protein D Alpha-1-antitrypsin E Acetoacetate

(C) An increased CRP predicts a greater likelihood for adverse events from atherogenesis. One benefit of 'statin' drugs is their CRP lowering effect.

A study of pathologic findings in the islets of Langerhans is performed. It is observed that insulitis may occur in the islets. The inflammatory infiltrate is predominantly composed of T lymphocytes. Which of the following is most likely to occur as a consequence of insulitis? A Neoplasia B Malabsorption C Ketoacidosis D Obesity E Sepsis

(C) An insulitis is seen with type I diabetes mellitus. Actually, it is rare to see it because by the time the patients present with overt diabetes mellitus, the islets are long gone.

Question 29 A 50-year-old man gives a history of chronic alcohol abuse. He has had bouts of abdominal pain in the past year. For the past month, he has had more frequent and worsening abdominal pain. Physical examination reveals right upper and left upper quadrant pain with guarding. An abdominal plain film radiograph reveals no free air, but there is extensive peritoneal fluid collection along with dilated loops of small bowel. An abdominal CT scan reveals a 7 to 8 cm cystic mass in the tail of the pancreas. Which of the following is the most likely diagnosis? A Islet cell adenoma B Acute pancreatitis C Pancreatic pseudocyst D Metastatic carcinoma E Pancreatic adenocarcinoma

(C) CORRECT. A pseudocyst is a complication of chronic pancreatitis seen most frequently in persons with a history of chronic alcoholism. The pseudocyst is an area of necrosis with a wall composed of granulation tissue.

A 16-year-old healthy adolescent is involved in a schoolyard gang fight and is stabbed in the chest with a knife in the left midclavicular line. He is taken to the emergency department and on arrival his blood pressure is barely obtainable. His lungs are clear to auscultation. His heart sounds are barely audible. Which of the following is the most useful therapeutic approach for this boy? A Coronary angioplasty B Aortic repair C Pericardiocentesis D Antibiotic therapy E Antiarrhythmic drugs

(C) CORRECT. A stab wound into heart can lead to hemopericardium with cardiac tamponade. The blood around the heart interferes with cardiac motion, reducing the ejection fraction, and diminishes the heart sounds.

A 45-year-old man was rushed to the hospital following the sudden onset of an episode of crushing substernal chest pain. He receives advanced life support measures. An EKG shows changes consistent with a large transmural anterolateral area of infarction involving wall of the left ventricle. He develops cardiogenic shock. Which of the following microscopic findings is most likely to be present in this area 4 days following the onset of his chest pain? A Fibroblasts and collagen deposition B Capillary proliferation and macrophages C Myofiber necrosis with neutrophils D Granulomatous inflammation E Perivascular lymphocytic infiltrates

(C) CORRECT. After 3 to 4 days following infarction, the muscle will still be necrotic and many neutrophils will persist, while macrophage infiltration will be beginning.

A 58-year-old man has had increasing difficulty swallowing for the past 6 months and has lost 5 kg. No abnormal physical examination findings are noted. Upper GI endoscopy reveals a nearly circumferential mass with overlying ulceration in the mid esophageal region. Biopsy of the mass reveals pink polygonal cells with marked hyperchromatism and pleomorphism. Which of the following is the most likely risk factor for development of his disease? A Iron deficiency B Helicobacter pylori infection C Chronic alcoholism D High fruit diet E Zenker diverticulum

(C) CORRECT. Chronic alcoholism and tobacco use are two of the most important risk factors for squamous cell carcinoma of the esophagus in the U.S., specifically related to squamous cell carcinomas of the mid-esophagus, as in this man. Zinc and molybdenum are trace elements in the diet whose absence increases the risk for carcinoma of the esophagus. Food contaminated with Aspergillus also carries a risk, as does food containing nitrosamines.

Question 19 A 40-year-old man has had mid epigastric pain and nausea for the past 2 months. On physical examination he has no abnormal findings. On upper GI endoscopy a solitary sharply demarcated 2-cm shallow gastric antral ulcer is seen. Which of the following laboratory test findings is most likely to be present in this man? A Gastric achlorhydria B Positive serology for antinuclear antibody C Positive urea breath test D Increased plasma cortisol E Elevated serum gastrin

(C) CORRECT. Helicobacter pylori organisms in the gastric mucus produce urease which will break down urea to ammonia and to CO2. For this urea breath test the patient drinks a measured quantity of a urea-containing solution with radiolabelled carbon. If the H. pylori organisms are present they metabolize the urea and release the radiolabelled carbon which is detected in exhaled air. Most gastric ulcers of this size are benign. Bleeding is a common complication of ulcer disease, seen in 25 to 33% of cases.

Question 37 A 35-year-old HIV positive woman known has had pain on swallowing for the past week. No abnormal physical examination findings are noted. Upper GI endoscopy is performed. There are 3 sharply circumscribed 0.3 to 0.8 cm ulcers in the lower esophagus. She is most likely to have infection with which of the following organisms? A Helicobacter pylori B Candida albicans C Herpes simplex virus D Mycobacterium avium-complex E Cytomegalovirus F Human herpes virus 8 G Cryptococcus neoformans

(C) CORRECT. Herpes esophagitis often has 'punched out' ulcerations. It is seen in immunocompromised patients, including those with HIV/AIDS.

Question 7 A 34-year-old healthy woman develops sudden severe abdominal pain. On physical examination she is afebrile. The pain is centered in the mid-epigastric region, though there is marked diffuse tenderness in all quadrants. Bowel sounds are absent. No masses are palpable. Laboratory studies show her serum amylase is 410 U/L and lipase is 610 U/L. Which of the following laboratory test findings is most likely to be present in this woman? A Hypercholesterolemia B Positive urea breath test C Hypercalcemia D Elevated sweat chloride E Positive serology for HBsAg

(C) CORRECT. Hypercalcemia is a less common cause for acute pancreatitis that can be found in persons with hyperparathyroidism. Once the pancreatitis has started, the formation of the chalky soap deposits of fat necrosis may draw off calcium to produce hypocalcemia.

A 45-year-old woman has had worsening shortness of breath for 3 years. She now has to sleep sitting up on two pillows. She has had difficulty swallowing for the past year. She has no history of chest pain. A month ago, she had a 'stroke' with resultant inability to move her left arm. She is afebrile. A chest radiograph reveals a near-normal left ventricular size with a prominent left atrial border. Which of the following conditions is most likely to account for her findings? A Essential hypertension B Cardiomyopathy C Mitral valve stenosis D Aortic coarctation E Patent foramen ovale

(C) CORRECT. Mitral valve stenosis leads to left atrial enlargement, but the left ventricle is usually small. THere is typically a 'fishmouth' shaped mitral valve that has stenosis as well as insufficiency, since it does not close completely. Most mitral valvular disease in adults results from rheumatic valvulitis. The episode(s) of rheumatic fever occurred years before and the scarring of the valve developed slowly.

A 23-year-old woman has had worsening malaise along with a malar skin rash persisting for 3 weeks. On physical examination, she has an audible friction rub on auscultation of the chest, along with a faint systolic murmur. An echocardiogram reveals small vegetations on the mitral valve and adjacent ventricular endocardium. Laboratory studies show a positive serologic test for anti-Smith antibody, with a titer of 1:2048. Which of the following is the most likely diagnosis? A Polyarteritis nodosa B Scleroderma, diffuse C Systemic lupus erythematosus D ANCA-associated granulomatous vasculitis E Adenocarcinoma of the pancreas

(C) CORRECT. Patients with systemic lupus erythematosus can develop Libman-Sacks endocarditis, but the sterile, non-infectious vegetations are never large and they rarely embolize, so the endocarditis is not clinically significant in most cases. She probably has a friction rub from fibrinous pericarditis as a result of uremia from renal failure.

A 26-year-old previously healthy woman has had worsening fatigue with dyspnea, palpitations, and fever over the past week. On physical examination her vital signs show T 38.9°C, P 104/minute, RR 30/minute, and BP 95/65 mm Hg. Her heart rate is slightly irregular. An ECG shows diffuse ST-T segment changes. A chest x-ray shows mild cardiomegaly. An echocardiogram shows slight mitral and tricuspid regurgitation but no valvular vegetations. Laboratory studies show a troponin I of 12 ng/mL. She recovers over the next two weeks with no apparent sequelae. Which of the following laboratory test findings best explains the underlying etiology for these events? A Anti-streptolysin O titer of 1:512 B Total serum cholesterol of 537 mg/dL C Echovirus serologic titer of 1:160 D Blood culture positive for Streptococcus, viridans group E ANCA titer of 1:80

(C) CORRECT. She has a febrile illness with findings that suggest myocarditis, which can have features of cardiomyopathy because of the diffuse myocardial involvement. The most likely organisms are enteroviruses (coxsackie B virus, echovirus) as well as adenoviruses.

A 2-year-old child has had failure to thrive for a year, becoming increasingly listless. On examination she is found to have a soft, rumbling systolic ejection murmur. An echocardiogram reveals a large membranous ventricular septal defect. Which of the following complications is she most likely to experience as an adult 2 decades later if this lesion remains untreated? A Rib notching B Mitral valve prolapse C Pulmonary hypertension D Myocardial infarction E Cardiac tamponade

(C) CORRECT. The left-to-right shunt from the VSD eventually leads to pulmonary hypertension and then reversal of the shunt (Eisenmenger complex) when the right heart pressures increase.

Question 12 A 39-year-old man is having a routine physical examination because of a history of colon cancer in his family. He has no abdominal tenderness or masses, and active bowel sounds are present. However, his stool is positive for occult blood. Colonoscopy is performed. There are 7 polyps found in the ascending colon: three of these are small 0.5 cm pedunculated tubular adenomas, three are 1 cm tubulovillous adenomas, and one is a 2 cm sessile villous adenoma in the cecum containing a focus of well differentiated adenocarcinoma. Which of the following is the most likely diagnosis? A Peutz-Jeghers syndrome B Chronic ulcerative colitis C Hereditary non-polyposis colon carcinoma D Familial polyposis coli E Gardner syndrome

(C) CORRECT. The number of polyps is not great in this case, but a cancer at his age suggests an aggressive course for a polyp. Many polyps and cancers of HNPCC involve the right (ascending) colon. This condition arises from abnormal mismatch repair genes and accounts for perhaps 1 to 3% of all colon cancers.

Question 30 A 39-year-old woman has experienced substernal burning pain following meals for the past 15 years. On physical examination there are no abnormal findings. Upper GI endoscopy is performed and there are 1 to 3 cm long tongues of erythematous mucosa extending from the gastroesophageal junction at the Z line upward into the lower esophagus. Biopsies are performed of this region and microscopic examination shows areas of gastric cardiac-type mucosa and intestinalized mucosa. Which of the following interpretations is most appropriate for this woman's findings? A She has a congenital anomaly B Her risk for squamous cell carcinoma is increased C She has chronic gastroesophageal reflux D Formation of a diverticulum may occur E She has iron deficiency anemia F Her anti-centromere antibody test is positive G Her consumption of alcohol is high

(C) CORRECT. There is columnar metaplasia in the lower esophagus with Barrett esophagus from esophageal reflux disease. A small percentage of these patients may develop adenocarcinoma.

Question 42 A 70-year-old previously healthy man notes blood-streaked stool and sees his physician. On physical examination his stool is positive for blood, though a lesion cannot be palpated by digital rectal examination. There are no palpable abdominal masses or organomegaly. There is no abdominal tenderness and bowel sounds are active. An appendectomy scar is present in the right lower quadrant. A colonoscopy is performed, and there is an area of obstruction from an encircling mass with superficial ulceration that is located at 20 cm above the anal verge. Which of the following risk factors was most likely to have been present for development of this lesion? A Human papillomavirus infection B Crohn disease C High fat diet D Diverticulosis E Prior abdominal surgery

(C) CORRECT. This is a colonic adenocarcinoma. At his age, this is likely a sporadic type of colon cancer, not an inherited condition nor a complication of inflammatory bowel disease, particularly in view of no past history of bowel disease. Increased fat intake and obesity are controversial as risk factors for cancer, but probably play a role. Reducing fat intake and maintaining an ideal body weight are good ways to help prevent cancers in general.

A 58-year-old man develops deep venous thrombosis during a hospitalization for prostatectomy. He exhibits decreased mental status 10 days postoperatively, with right hemiplegia. A CT scan of the head shows an acute cerebral infarction in the distribution of the left middle cerebral artery. A chest radiograph reveals cardiac enlargement and prominence of the main pulmonary arteries consistent with pulmonary hypertension. Laboratory studies show a serum troponin I of <0.4 ng/mL. Which of the following lesions is most likely to be present on echocardiography? A Coarctation of the aorta B Tetralogy of Fallot C Atrial septal defect D Pulmonic stenosis E Dextrocardia

(C) CORRECT. This is the infamous 'paradoxical embolus' from right to left. This can only happen if there is a defect that allows passage from right-to left. This can happen across a patent foramen ovale. In this case, the pulmonary hypertension suggests that there may have been a shunt persistent for a long time--a so-called Eisenmenger complex. An atrial or a ventricular septal defect can provide the shunt.

Question 41 A 41-year-old man is found in an obtunded state and taken to the hospital. On admission physical examination he is icteric. His abdomen is enlarged with a fluid wave. An abdominal CT scan shows extensive intraperitoneal fluid and a uniformly enlarged liver that has decreased attenuation (decreased brightness). Laboratory studies show total protein 6.5 g/dL, albumin 2.8 g/dL, total bilirubin 4.8 mg/dL, AST of 563 U/L, ALT 317 U/L, alkaline phosphatase 55 U/L, and ammonia 91 micromol/L. A liver biopsy is performed and microscopically demonstrates abundant Mallory hyaline, neutrophilic infiltrates, hepatocyte necrosis, portal fibrosis, and extensive macrovesicular steatosis. Which of the following is the most likely diagnosis? A Acute hepatitis A infection B Sclerosing cholangitis C Alcoholic hepatitis D Chronic hepatitis B infection E Acetaminophen toxicity

(C) CORRECT. This is the typical appearance of acute sclerosing hyaline necrosis with alcoholic hepatitis. It is usually seen in the setting of chronic alcoholism with a superimposed recent episode of binge drinking. It is the one condition intrinsic to liver in which many neutrophils are present.

Question 9 A 45-year-old man has had vague abdominal pain and nausea for the past 3 years. This pain is unrelieved by antacid medications. He has no difficulty swallowing and no heartburn following meals. On physical examination there are no abnormal findings. Upper GI endoscopy reveals antral mucosal erythema, but no ulcerations or masses. Biopsies are taken, and microscopically there is a chronic non-specific gastritis. Which of the following conditions is most likely to be present in this man? A Zollinger-Ellison syndrome B Pernicious anemia C Helicobacter pylori infection D Adenocarcinoma E Crohn disease F Mixed connective tissue disease

(C) CORRECT. This organism is often seen with chronic gastritis.

Question 11 A 31-year-old woman has a 10 year history of intermittent, bloody diarrhea. She has no other major medical problems. On physical examination there are no lesions palpable on digital rectal examination, but a stool sample is positive for occult blood. Colonoscopy reveals a friable, erythematous mucosa with focal ulceration that extends from the rectum to the mid-transverse colon. Biopsies are taken and all reveal mucosal acute and chronic inflammation with crypt distortion, occasional crypt abscesses, and superficial mucosal ulceration. This patient is at greatest risk for development of which of the following conditions? A Acute pancreatitis B Diverticulitis C Sclerosing cholangitis D Appendicitis E Perirectal fistula F Non-Hodgkin lymphoma

(C) CORRECT. This patient has ulcerative colitis (UC). One of the extraintestinal manifestations of this form of inflammatory bowel disease is sclerosing cholangitis, which can still occur even after the colon is removed.

Question 32 A 45-year-old man has had malabsorption for the past year associated with a low volume diarrhea. He also has a polyarthritis and complains of occasional visual hallucinations. On physical examination there are no joint deformities. A stool sample is negative for occult blood. An abdominal CT scan reveals no masses, only generalized lymphadenopathy. On upper GI endoscopy, there are no esophageal or gastric lesions, but there are broad, flattened villi in the duodenum. Biopsies of the duodenum reveal numerous PAS-positive macrophages in the submucosa. Which of the following therapies is most likely to be useful for this man? A Gluten-free diet B Corticosteroids C Antibiotics D Segmental duodenal resection E Antacids F Aromatherapy

(C) CORRECT. Whipple disease is rare. It can affect multiple organs, including the brain. The organisms causing Whipple disease are actinomycetes (Tropheryma whippelii). The foamy macrophages can be in the small intestinal submucosa, adjacent lymph nodes, or at extraintestinal sites.

Question 38 A 30-year-old man has had a low volume, bloody, mucoid diarrhea for 3 weeks accompanied by lower abdominal pain. On physical examination he has no abdominal masses and mild diffuse lower abdominal tenderness. His stool is positive for occult blood. Colonoscopy reveals an erythematous, friable colonic mucosa extending from the rectum to the splenic flexure. Colonic biopsies reveal mucosal ulceration with crypt abscesses. Which of the following complications is he most likely to develop? A Bowel perforation and peritonitis B Fistula formation to the skin C Ischemic bowel necrosis D Colonic adenocarcinoma E Hepatic micronodular cirrhosis

(D) CORRECT. Chronic ulcerative colitis carries a significant risk for development of colonic adenocarcinoma 2 or 3 decades after onset.

A 63-year-old man has had insulin dependent diabetes mellitus for over two decades. The degree of control of his disease is indicated by the laboratory finding of hemoglobin A1C 10.1%. He has noted episodes of abdominal pain following meals. These episodes have worsened over the past year. On physical examination, there are no masses and no organomegaly of the abdomen, and he has no tenderness to palpation. Which of the following pathologic findings is most likely to be present in this man? A Ruptured aortic aneurysm B Hepatic infarction C Mesenteric artery occlusion D Acute pancreatitis E Chronic renal failure

(C) He has 'abdominal angina' from diminished blood flow to the bowel as a consequence of severe atherosclerosis. Persons with diabetes mellitus may have this finding, because all branches of major arteries to the bowel are affected by atherosclerosis.

At autopsy, the kidneys of a 44-year-old woman who died suddenly are found to be of normal size. Their surfaces appear finely granular. There are small hemorrhages noted. The cortices appear pale. Microscopically, many small renal arteries and arterioles demonstrate concentric intimal thickening with marked luminal narrowing. These findings are most likely to be present as a result of which of the following underlying diseases? A Amyloidosis B Systemic lupus erythematosus C Scleroderma D Rheumatoid arthritis E Viral hepatitis F Diabetes mellitus

(C) Hyperplastic arteriolosclerosis is typically seen in association with severe hypertension, which can complicate prior 'essential' hypertension or occur with progressive systemic sclerosis (scleroderma).

A 10-year-old previously healthy child has been noted by her parents to be constantly thirsty. She is consuming large amounts of soft drinks. She is urinating often. Her diet and exercise patterns have not changed, except for an increased appetite, yet she appears cachectic and has lost 7 kg over the past 4 months. On physical examination there are no abnormal findings, other than peripheral muscle wasting and weakness. Which of the following laboratory findings would you most strongly suspect is present in this girl? A Increased blood insulin B Decreased blood glucagon C Ketonuria D Increased serum osmolality E Decreased plasma H+ (alkalosis) F Decreased plasma cortisol

(C) Ketonuria is typical for type I diabetes mellitus. The findings of polydipsia, polyuria, and polyphagia are present in this case. The absolute decrease in insuling leads to a catabolic state, with underutilization of carbohydrates, and lipolysis with metabolism of fatty acids to produce ketone bodies.

A 49-year-old woman has experienced marked pain in her lower extremities on ambulation more than 300 meters for the past 5 months. On physical examination, her lower extremities are cool and pale, without swelling or erythema. No dorsalis pedis or posterior tibial pulses are palpable. Her body mass index is 32. She is a smoker. Which of the following abnormalities of the vasculature is most likely to account for these findings? A Lymphatic obstruction B Arteriolosclerosis C Atherosclerosis D Medial calcific sclerosis E Venous thrombosis

(C) She has claudication from severe peripheral arterial atherosclerosis, most likely from the iliac arteries down. Her major risk factor is obesity that promotes insulin resistance and diabetes mellitus that leads to atherosclerosis.

A 66-year-old woman has the sudden loss of movement on part of the left side of her body. She has smoked a pack of cigarettes a day for the past 45 years. She has vital signs including T 37.1°C, P 80/minute, RR 16/minute, and BP 160/100 mm Hg. A cerebral angiogram reveals occlusion of a branch of her middle cerebral artery. Laboratory findings include a hemoglobin A1C of 9%. Which of the following components of blood lipids is most important in contributing to her disease? A Chylomicrons B Lipoprotein lipase C Oxidized LDL D VLDL E HDL cholesterol

(C) She has had a 'stroke' which is most often a consequence of cerebral atherosclerosis or embolic disease from the heart as a consequence of ischemic heart disease from atherosclerosis. LDL brings cholesterol to arterial walls, and when increased LDL is present or when there is hypertension, smoking, and diabetes, there is more degradation of LDL to oxidized LDL which is taken up into arterial walls via scavenger receptors in macrophages to help form atheromas.

A study is performed involving persons who have a history of diabetes mellitus type 1 or type 2. These patients are found to have cellular injury that results from glycosylation end products and from sorbitol accumulation within cells. The same patients are also shown to have ischemic tissue damage from accelerated and advanced atherosclerosis. Which of the following complications is most likely to result from atherosclerosis in these patients? A Hepatic failure B Impotence C Stroke D Cataracts E Retinopathy

(C) Stroke from cerebral atherosclerosis or from embolization of mural thrombi from a heart involved with ischemic injury as a consequence of atherosclerosis....

A 54-year-old previously healthy woman is hospitalized for pneumonia. On the 10th hospital day she is found to have swelling and tenderness of her right leg, which has developed over the past 48 hours. Raising the leg elicits pain. An ultrasound examination reveals findings suggestive of femoral vein thrombosis. Which of the following conditions is most likely to have contributed the most to the appearance of these findings? A Trousseau syndrome B Protein C deficiency C Immobilization D Pregnancy E Chronic alcohol abuse F Hypertension

(C) The immobilization while in hopsital would predispose to thrombosis of leg veins. This is the most common cause for deep venous thrombosis.

A 61-year-old man has the sudden onset of severe chest pain. Vital signs include T 37°C, P 102/minute, RR 20/minute, and BP 80/40 mm Hg. An electrocardiogram demonstrates changes that are consistent with myocardial ischemia involving the left lateral ventricular free wall. He is given thrombolytic therapy with tissue plasminogen activator (tPA) 3 hours after the onset of chest pain. However his serum creatinine kinase is found to be 450 U/L 3 hours after this therapy. Which of the following cellular events has most likely occurred? A Cellular regeneration B Drug-induced necrosis C Reperfusion injury D Increased synthesis of creatine kinase E Myofiber atrophy

(C) The restoration of blood flow is helpful if the existing cell damage is not great, so further damage can be prevented. However, the reperfusion of damaged cells results in generation of oxygen free radicals to produce a reperfusion injury.

A 25-year-old man experiences chest pain on exercise when he attempts to climb three flights of stairs. This pain is relieved by sublingual nitroglycerin. He is 178 cm tall and weighs 101 kg. His blood pressure is 130/85 mm Hg. Laboratory studies show a total serum cholesterol of 550 mg/dL with an HDL cholesterol component of 25 mg/dL. The blood glucose is 120 mg/dL. He is worried about these findings because his brother died of a myocardial infarction at age 34. Which of the following conditions is this man most likely to have? A Diabetes mellitus, type II B Malignant hypertension C Familial hypercholesterolemia D Cushing syndrome E Morbid obesity

(C) The very high cholesterol with symptoms of coronary artery disease at such a young age, coupled with the family history, are all consistent with familial hypercholesterolemia. In most persons with hypercholessterolemia from multifactorial causes, including diet and exercise patterns, the cholesterol rarely exceeds 400 mg/dL.

A 72-year-old man suffered a myocardial infarction involving half the left ventricular free wall 3 months ago. He now has increasing dyspnea and orthopnea. On echocardiography his ejection fraction is 29%. On examination he has poor capillary filling in hands and feet. A chest x-ray shows pulmonary edema. Which of the following laboratory test analytes is most likely to be increased in this man at this point in time? A Sodium B Creatine kinase C Natriuretic peptide D Hematocrit E Sedimentation rate

(C) With congestive heart failure, there is volume overload that triggers an increase in natriuretic peptide, typically measured as the b-type (BNP). This hormone normally leads to natriuresis, diuresis, and vasodilation, lessening the strain on the myocardium.

A 57-year-old woman has experienced episodes of altered mental status for the past month. On physical examination, she has bilateral carotid artery bruits. She is given folic acid supplementation. Which of the following laboratory test findings is she most likely to have? A Factor V Leiden mutation B Factor VIII deficiency C Increased carcinoembryonic antigen D Homocysteinemia E Increased HDL cholesterol

(D) An elevated plasma homocysteine level is a risk for atherosclerosis as well as thrombosis. Her findings point to transient ischemic attacks (TIAs) with risk for stroke. The carotid bruits represent arterial narrowing as the result of atherosclerosis.

A 37-year-old previously healthy man has had worsening dyspnea along with peripheral edema for the past two years. On physical examination he has diffuse crackles auscultated over both lungs. A chest radiograph shows that the heart nearly fills the chest. A chest CT scan demonstrates a 10 cm mass involving the right ventricle that appears to have areas of hemorrhage and necrosis within it. Which of the following neoplasms is this man most likely to have? A Rhabdomyosarcoma B Mesothelioma C Myxoma D Angiosarcoma E Papillary fibroelastoma F Kaposi sarcoma G Rhabdomyoma

(D) CORRECT. Angiosarcoma is a rare cardiac neoplasm (all primary cardiac neoplasms are rare) but the size alone suggests a malignancy.

A 45-year-old man has had a fever and a productive cough for the past 3 days. On physical examination there is dullness to percussion over the right upper lung. His temperature is 37.9 C. A chest radiograph reveals right upper lobe consolidation. Laboratory findings include serum total protein of 6.0 g/dL, albumin 2.7 g/dL, AST 185 U/L, ALT 98 U/L, total bilirubin 1.0 mg/dL, alkaline phosphatase 31 U/L, and prothrombin time 20 sec. He does not respond to antibiotic therapy and dies. He is found at autopsy to have a 2500 gm liver (normal for his size up to 1800 gm) that microscopically shows most of the hepatocytes to be filled with large lipid droplets. Which of the following conditions is the most likely underlying cause of death? A Alpha-1-antitrypsin deficiency B Wilson disease C Acute hepatitis C D Chronic alcoholism E Biliary tract lithiasis

(D) CORRECT. Big fatty livers are often seen in conjuction with chronic alcoholism. In the absence of a history of chronic alcohol abuse, non-alcoholic fatty liver (NAFL) is the likely cause, and NAFL can be associated with obesity and diabetes mellitus. Microscopically, the pattern will be macrovesicular steatosis, with large lipid vacuoles filling hepatocytes.

A 49-year-old woman had atrial fibrillation that was poorly controlled, even with amiodarone therapy. She suffered a 'stroke' and died. At autopsy, her 600 gm heart is noted to have a mitral valve with partial fusion of the leaflets along with thickening and shortening of the chordae tendineae. There is an enlarged left atrium filled with mural thrombus. Which of the following underlying causes of death is she most likely to have? A Systemic lupus erythematosus B Coronary atherosclerosis C Marantic endocarditis D Rheumatic heart disease E Cardiac amyloidosis

(D) CORRECT. Bouts of rheumatic fever can eventually lead to rheumatic mitral stenosis with left atrial enlargement.

Question 8 After a summertime camping trip in the Cascade mountains of Washington state, a 29-year-old man has developed a mild watery diarrhea for the past week. While on the trip he drank water from the mountain streams. A physical examination reveals no abdominal pain or masses. He is afebrile. Bowel sounds are present. His stool is negative for occult blood. The diarrhea abates in 3 weeks. His two children are similarly affected. Which of the following infectious agents most likely caused his disease? A Rotavirus B Shigella flexneri C Vibrio cholerae D Giardia lamblia E Entamoeba histolytica F Cryptosporidium parvum G Salmonella enteritidis H Norovirus

(D) CORRECT. Giardiasis is typically a non-life threatening nuisance in immunocompetent persons. The organisms are found in contaminated water, particularly in areas such as apparently pristine, remote, mountains not considered to be a risk for infectious diseases. He had not read his Sierra Club guide in regard to treatment of drinking water while camping.

A 60-year-old man had chest pain and was hospitalized. On the first day of admission, his troponin I is elevated. A coronary angiogram revealed 75% stenosis of the anterior interventricular (left anterior descending) artery. Four days later he suddenly becomes worse, with marked hypotension. A pericardiocentesis is performed and returns 150 cc of bloody fluid. Which of the following microscopic findings is most likely to be present in his left ventricular myocardium at the time of this hypotensive episode? A Extensive transmural collagen deposition B Lymphocytic infiltrates C Coronary arterial dissection D Necrosis with neutrophils and macrophages E Interstitial edema and loss of myofiber cross striations

(D) CORRECT. He has had an acute myocardial infarction complicated by rupture. This is a typical complication about 3 to 7 days following the onset of infarction. 75% arterial narrowing is the point at which coronary occlusion becomes very serious with increased risk for acute coronary syndromes.

Question 27 A 32-year-old man has had lower abdominal pain for the past 12 hours. On physical examination there is tenderness to palpation in the right lower quadrant. Laparoscopic appendectomy is performed. On microscopic examination of the resected appendix by the pathologist, all the inflammation is limited to the serosa. What should the pathologist most strongly suspect in this case? A Mild early acute appendicitis B Chronic appendicitis C Polyarteritis nodosa D Peritonitis E Normal appendix

(D) CORRECT. If only the serosa is inflamed, then something other than the appendix led to the inflammation -- possibly a perforation, and this should be communicated to the surgeon, because the causative condition must be diagnosed and treated.

A 19-year-old woman has had increasing malaise for the past 5 months. On physical examination she has a cardiac murmur characterized by a mid systolic click. An echocardiogram demonstrates mitral insufficiency with upward displacement of one leaflet. There is aortic root dilation to 4 cm. She has a dislocated right ocular crystalline lens. A year later she dies suddenly and unexpectedly. The medical examiner finds a prolapsed mitral valve with elongation, thinning, and rupture of chordae tendineae. A mutation involving which of the following genes is most likely to be present in this patient? A Beta-myosin B CFTR C FGFR D Fibrillin E Spectrin F Dystrophin

(D) CORRECT. Marfan syndrome is a connective tissue disorder that is associated with floppy mitral valve and also with cystic medial necrosis that predisposes to aortic dissection. The sudden cardiac death in this case is due to the valvular abnormality.

A 17-year-old girl experiences syncope while out running for exercise one afternoon, as she has done for many years. Physical examination, chest radiograph, head CT scan, CBC, and chemistry panel are all normal. Over the next year, she develops mild dyspnea and fatigue. She experiences several episodes of near-syncope. After another syncopal episode, she is referred to a cardiologist who orders an EKG that shows changes of left ventricular hypertrophy and broad Q waves. An echocardiogram reveals left ventricular and septal hypertrophy, small left ventricle, and reduced septal excursion. The septum has a 'ground glass' appearance. Which of the following is the most likely microscopic feature of her disease process? A Aschoff bodies B Lymphocytic infiltrates C Pericarditis D Myofiber disarray E Atheroma formation

(D) CORRECT. Myofiber disarray is the key feature of hypertrophic cardiomyopathy. The abnormal myocardium can be the focus for development of arrhythmias.

A 53-year-old man has had malaise for the past 3 months. On physical examination he is afebrile. On auscultation of the chest, heart sounds are distant and there is a friction rub. An echocardiogram shows a pericardial fluid collection. A pericardiocentesis yields 10 mL of bloody fluid. Which of the following conditions is most likely to give rise to these findings? A Autoimmune disease B Chronic renal failure C Rheumatic fever D Metastatic carcinoma E Acute myocardial infarction

(D) CORRECT. Pericardial tumor and tuberculosis are the typical causes for a hemorrhagic pericarditis.

Question 17 A 20-year-old man is healthy but has a family history of colon cancer with onset at a young age. There are no abnormal physical examination findings. He undergoes colonoscopy and there are over 200 tubular adenomas ranging in size from 0.2 to 1 cm on gross inspection and microscopic examination of biopsies. Which of the following genetic diseases is he most likely to have? A Hereditary non-polyposis colon carcinoma syndrome B Gardner syndrome C Peutz-Jeghers syndrome D Adenomatous polyposis coli E Multiple endocrine neoplasia

(D) CORRECT. Persons with familial polyposis caused by abnormal APC genes should have a colectomy for this reason. By late childhood to young adulthood, one or more of the polyps will give rise to a malignancy.

A 72-year-old woman has had no major illnesses throughout her life. She has had 3 syncopal episodes during the past 2 weeks. Over the past 2 days she has developed shortness of breath and a cough with production of frothy white sputum. On physical examination she is afebrile. Her blood pressure is 135/90 mm Hg. She has no peripheral edema. A chest radiograph reveals a prominent left heart border in the region of the left ventricle, but the other chambers do not appear to be prominent. There is marked pulmonary edema. Laboratory studies show a total serum cholesterol of 170 mg/dL. Which of the following is the most likely diagnosis? A Acute rheumatic fever B Mitral valve insufficiency C Atherosclerotic aortic aneurysm D Calcific aortic stenosis E Infective endocarditis

(D) CORRECT. Senile calcific aortic stenosis is a condition in which there is gradual calcification of an aortic valve with three cusps. The condition is seen in the elderly and is idiopathic. Aortic valvular stenosis may not manifest itself clinically until there is critical narrowing of the outflow orifice to less than 1 square centimeter. Aortic valve disease can remain silent and then suddenly result in symptoms.

A 24-year-old woman with rheumatic heart disease becomes febrile. On physical examination she has a systolic murmur. An echocardiogram shows vegetations of the aortic valve cusps. A blood culture is positive for Staphylococcus epidermidis. She receives a porcine bioprosthesis because of her desire to have children and not to take anticoagulant medication. After ten years, she must have this prosthetic valve replaced. Which of the following pathologic findings in the bioprosthesis has most likely led to the need for replacement? A Dehiscence B Endocarditis C Strut failure D Calcification E Thrombosis

(D) CORRECT. The bioprosthesis has the advantage of not requiring anticoagulation, but it does not wear well with time, and typically must be replaced within 5 to 10 years when its leaflets undergo progressive calcification leading to stenosis.

Question 36 A 47-year-old woman has a history of chronic alcohol abuse. She has chronic arthritis for which she has taken over-the-counter medications for the past 5 years. She has developed increasing malaise and nausea for the past week. On physical examination she displays decreased alertness. There are no abdominal masses or evidence for organomegaly. There is no abdominal pain or tenderness. Her stool is negative for occult blood. Laboratory findings include: WBC count 6300/uL, Hgb 12.5 g/dL, Hct 37.2%, MCV 101 fL, platelets 185,000/uL, total protein 6.3 g/dL, albumin 3.3 g/dL, alkaline phosphatase 75 U/L, AST 340 U/L, ALT 330 U/L, lipase 39 U/L, total bilirubin 1.9 mg/dL, and direct bilirubin 0.9 mg/dL. Ingestion of which of the following medications is most likely to have contributed to the development of these findings? A Aspirin B Ibuprofen C Indomethacin D Acetaminophen E Rofecoxib F Morphine G Meperidine

(D) CORRECT. The elevated AST and ALT point to liver necrosis. Chronic alcoholism makes acetaminophen toxicity more likely by depleting the glutathione that helps detoxify the metabolites.

A 50-year-old man has the sudden onset of substernal chest pain. The pain persists for the next three hours. He then becomes short of breath and diaphoretic. He goes to the emergency department and on physical examination his vital signs include T 37°C, P 100/minute, RR 26/minute, and BP 130/90 mm Hg. A chest x-ray shows a slightly enlarged heart and mild pulmonary edema. An EKG shows ST segment elevation in anterior leads V1 - 6. Which of the following serum laboratory test findings is most likely to be present in this man? A Urea nitrogen of 110 mg/dL B Sodium of 115 mmol/L C ALT of 876 U/L D Troponin I of 32 ng/mL E HDL cholesterol of 55 mg/dL

(D) CORRECT. The findings suggest an early ischemic event as part of an acute coronary syndrome with developing myocardial infarction. The troponin I can be elevated within a few hours, and it will remain elevated for 10 to 14 days, while the CK-MB will peak in a day and subside by 3 days.

A 20-year-old primigravida delivers a term baby girl following an uncomplicated pregnancy. No anomalies are noted at the time of birth. Five weeks later, the mother brings the baby to the clinic because she has difficulty breathing and occasionally turns pale. On physical examination a pansystolic murmur is audible. Which of the following congenital cardiac anomalies is most likely to be present in this infant? A Hypertrophic subaortic stenosis B Hypoplastic left heart syndrome C Coarctation of the aorta D Ventricular septal defect E Bicuspid aortic valve

(D) CORRECT. The most common congenital cardiac defect in livebirths is a VSD. The baby may first become symptomatic when the pulmonary arteries dilate fully after the first month of life and the shunting from left-to-right increases to promote congestive heart failure.

A 44-year-old woman dies as a consequence of a 'stroke'. At autopsy, she is found to have a large right basal ganglia hemorrhage. She has an enlarged 550 gm heart with predominantly left ventricular hypertrophy. Her kidneys are small, about 80 gm each, with cortical scarring, and microscopically they demonstrate small renal arterioles that have luminal narrowing from concentric intimal thickening. Which of the following is the most likely condition associated with her findings? A Autosomal dominant polycystic kidney disease B Diabetes mellitus, type II C Hypercholesterolemia D Malignant hypertension E Monckeberg's sclerosis

(D) CORRECT. The small arteries of the kidney are affected by hyperplastic arteriolosclerosis. Malignant hypertension with markedly elevated blood pressure is often preceded by chronic hypertension that leads to left ventricular hypertrophy. Hypertension is a risk for CNS hemorrhage.

Question 15 A 60-year-old man has had anorexia, vomiting, and vague abdominal pain accompanied by weight loss of 6 kg over the past 2 months. Physical examination reveals supraclavicular non-tender lymphadenopathy. He becomes progressively cachectic and dies. At autopsy the stomach is shrunken with the gastric wall thickened to 1 cm and with extensive overlying mucosal erosions. Multiple tan umbilicated masses from 1 to 4 cm in size are scattered over the surface of the liver. Which of the following conditions most likely preceded development of his terminal illness? A Human immunodeficiency virus infection B Diabetes mellitus, type I C Chronic alcoholism D Pernicious anemia E A diet high in fresh fruits F Use of NSAIDS

(D) CORRECT. This is linitis plastica of the stomach, which typically has a signet ring cell pattern of adenocarcinoma diffusely infiltrating the stomach. Autoimmune gastritis is a risk factor for this condition.

A 45-year-old man feels some crushing chest pain along with numbness in his left arm after shoveling 15 cm of snow off his driveway. Three hours later he collapses and is taken to the emergency room. Which of the following laboratory tests run on a blood specimen is most useful in this situation? A Total white blood cell count B Glucose C Platelet count D Creatine kinase E Amylase

(D) Elevations in CK enzyme are going to be seen acutely with myocardial infarction beginning within 3 hours and remaining for 3 days. The total CK reflects changes in any striated muscle, and is not specific for cardiac muscle. The CK-MB fraction is most specific to myocardium.

A 44-year-old woman has a family history of heart disease. Her father and mother both developed myocardial infarction and congestive heart failure as a result of occlusive coronary atherosclerosis. A dietary modification to include consumption of which of the following is most likely to reduce her risk for ischemic heart disease? A 40% of total caloric intake as fat B Increased saturated fat C Foods with cholesterol D Cold water fish oil E Fat found in beef products F Hydrogenated oils with trans-fats

(D) Fish oils diminish arachidonic acid metabolites and reduce platelet aggregation.

A 56-year-old reports reduced exercise tolerance over the past 5 years. In the past year he has noted chest pain after ascending a flight of stairs. He smokes 2 packs of cigarettes per day. On examination he has a blood pressure of 155/95 mm Hg. His body mass index is 30. Laboratory findings include a total serum cholesterol of 245 mg/dL with an HDL cholesterol of 22 mg/dL. Which of the following vascular abnormalities is he most likely to have? A Hyperplastic arteriolosclerosis B Lymphedema C Medial calcific sclerosis D Atherosclerosis E Deep venous thrombosis F Plexiform arteriopathy

(D) He has multiple risk factors for atherosclerosis, including his weight, smoking, hypertension, and high total cholesterol with low 'good' HDL cholesterol. His findings suggest coronary artery disease with risk for an acute coronary syndrome.

A 27-year-old woman had a hemoglobin A1C of 7.9% noted during a prenatal visit. She gives birth to a 4350 gm baby at 37 weeks gestation. Just after the delivery, the baby becomes irritable and displays seizure activity. Which of the following laboratory findings is most likely to be found in the baby: A Decreased hemoglobin A1C B Increased serum osmolality C Hyperlipidemia D Hypoglycemia E Ketoacidosis

(D) Infants of diabetic mothers are at risk for hypoglycemia following delivery, because they have islet hypertrophy and hyperplasia, and the increased islet production of insulin carries into the immediate postpartum period.

A 53-year-old man has the sudden onset of chest pain. He is found to have a serum troponin I of 5 ng/mL. A year later he has reduced exercise tolerance. An echocardiogram reveals an akinetic segment of left ventricle, and he has reduced cardiac output, with an ejection fraction of 25%. He then experiences a transient ischemic attack (TIA). His serum troponin I is now <0.5 ng/mL. Thrombus formation involving which of the following locations is most likely to have put him at greatest risk for the TIA? A Cerebral vein B Vertebral artery C Superior vena cava D Left ventricle E Coronary artery F Saphenous vein

(D) Mural thrombi can form over the damaged area of ventricular wall following myocardial infarction. This can happen acutely overlying the necrotic myocardium; it can occur remotely in a ventricular aneurysm. Portions of the mural thrombus can break off and embolize via the systemic arterial circulation to places such as the cerebral circulation.

Some cells demonstrate glucose uptake from the blood regardless of the plasma insulin level. In persons who have had persistent hyperglycemia for years, cellular injury can occur. Which of the following cell types is most likely to show injury from hyperglycemia? A Cardiac myocytes B Fibroblasts C Steatocytes D Neurons E Smooth muscle cells.

(D) Neurons do not require insulin for glucose uptake. The excess glucose diffusing into the cells is shunted into the sorbitol pathway and can lead to osmotic injury, resulting in neuropathy.

A 29-year-old woman is involved in a motor vehicle accident that results in severe lacerations to her lower extremities, along with blunt abdominal trauma. In the emergency room she is noted to have cool, pallid skin. She has vital signs showing T 36.9°C, P 110/minute, RR 26/minute, and BP 70/30 mm Hg. She has decreased urine output. Which of the following laboratory findings on a blood sample from this patient is most likely to be present? A Hematocrit of 54% B Glucose of 181 mg/dL C PaO2 of 20 mm Hg D Lactic acid of 4.8 mmol/L E Troponin I of 4 ng/mL

(D) She has marked blood loss with shock. There will be vasoconstriction in skin and soft tissue in response to the hypovolemia. Decreased renal blood flow from shock may lead to acute tubular necrosis. The lack of tissue perfusion with shock leads to increased anaerobic glycolysis and lactic acidosis.

A 53-year-old woman is found on a routine physical examination to have vital signs with T 37°C, P 78/minute, RR 16/minute, and BP 165/110 mm Hg. There are no other significant findings. She has an abdominal ultrasound examination that shows the right kidney to be atrophic. Angiography reveals markedly reduced blood flow to the right renal artery from an occlusion at the orifice in the abdominal aorta. Which of the following laboratory findings is she most likely to have? A Serum sodium of 161 mmol/L B Serologic evidence of anti-cardiolipin antibody C Prothrombin time of 25 seconds D Plasma renin activity of 4.8 ng/mL/hr supine E Serum lactic acid of 5.5 mmol/L

(D) She has renal artery stenosis that is reducing renal blood flow on the right and simulating the JG cells to secrete renin to try and raise blood pressure to increase renal blood flow.

A 45-year-old man dies suddenly and unexpectedly. The immediate cause of death is found to be a hemorrhage in the right basal ganglia region. On microscopic examination his renal artery branches have concentric endothelial cell proliferation which markedly narrows the lumen, resulting in focal ischemia and hemorrhage of the renal parenchyma. An elevation in which of the following substances in his blood is most likely to be associated with these findings? A Ammonia B Calcium C Cholesterol D Renin E Troponin I F Triglyceride G C-reactive protein

(D) The findings suggest hyperplastic arteriolosclerosis, which accompanies malignant hypertension. Reduced renal blood flow increases renin, driving hypertension.

A 52-year-old man has an ulcerated area on the sole of his foot that has not healed for 2 months. He is 180 cm tall, weighs 126 kg, and has continued to gain weight gradually. He has not had any major illnesses. His blood pressure is normal. Which of the following laboratory tests performed on serum from a blood sample would be most useful in elucidating the underlying cause for his problem: A Antithrombin III B Cortisol C Creatine kinase D Glucose E Carcinoembryonic antigen

(D) The history suggests diabetes mellitus, most likely type II, and persistent hyperglycemia would confirm the diagnosis.

In a clinical study of patients with diabetes mellitus, a group of patients is found who have had blood glucose measurements ranging from 140 to 180 mg/dL for at least 10 years. Rectal biopsies from these patients now show that there is a form of osmotic cellular injury present in arterioles. This form of injury is most likely to be manifested elsewhere in the body by which of the following complications? A Cerebral infarction B Gastric adenocarcinoma C Congestive heart failure D Impotence E Pyelonephritis

(D) The hyperglycemia leads to formation of sorbitol in tissues not requiring insulin for glucose uptake, resulting in osmotic cellular injury. This can occur in small vessels, retina, kidney, and nerves. The failure of erection and ejaculation results from diabetic neuropathy.

A 34-year-old previously healthy woman notes that she has bruises form on her arms and legs with just minor trauma. Physical examination reveals areas of purpura from 1 to 3 cm in size over her trunk and extremities, but no swelling, warmth, or erythema. Peripheral pulses are all palpable and full. Her blood pressure is 110/70 mm Hg. An ultrasound examination of her lower extremities with Doppler flow measurement reveals no evidence for thrombosis. Laboratory findings include serum urea nitrogen of 16 mg/dL, LDH 300 U/L, total protein 6.9 g/dL, albumin 5.3 g/dL, alkaline phosphatase 50 U/L, AST 40 U/L, and ALT 20 U/L. Which of the following additional laboratory findings is most likely to be present in this patient? A Hyperglycemia B Hypercholesterolemia C Lactic acidosis D Thrombocytopenia E Hypoprothrombinemia F Anemia

(D) The platelets are responsible for dealing with small leaks in small vessels. Thrombocytopenia is marked by petechiae and purpura. She does not have evidence for peripheral vascular disease, since her circulation is good. Venous thrombosis should lead to swelling and tenderness.

A 52-year-old woman has experienced marked substernal, crushing chest pain for the past 3 hours. Her vital signs show T 36.9°C, P 90/minute, RR 18/minute, and BP 100/60 mm Hg. Laboratory studies include a serum creatine kinase MB fraction of 10 microgm/L as well as a serum troponin I of 4.5 ng/mL. Which of the following findings is the best evidence for the presence of a coronary arterial thrombus as the etiology for her chest pain? A Total serum cholesterol of 300 mg/dL B Large size of the infarction by scintigraphic scanning C 80% coronary occlusion by angiography D Response to thrombolytic therapy E Hemoglobin A1C of 10.1%

(D) The purpose of thrombolytic therapy is to lyse the thrombus and restore blood flow. Many acute coronary events are the result of thrombus formation on pre-existing atheromas. Low dose aspirin therapy helps prevent such events.

A 70-year-old man has noted coldness and numbness of his lower left leg, increasing over the past 4 months. He also experiences pain in this extremity when he tries walking more than the distance of half a city block. On physical examination, his dorsalis pedis, posterior tibial, and popliteal artery pulses are not palpable. Which of the following laboratory test findings is he most likely to have? A Protein S deficiency B Blood culture with Staphylococcus aureus C Decreased arterial oxygen saturation D Hyperglycemia E Hypercalcemia

(D) This is peripheral arterial vascular disease from severe atherosclerosis, which is promoted by diabetes mellitus. The absence of pulses defines this as an arterial process, as does the claudication (pain with exercise). Thrombophlebitis is a venous process and leads to swelling and pain in the leg, but not loss of pulses..

During hospitalization, a 40-year-old woman develops thrombophlebitis. She recovers and is discharged. She returns to her job as an electrician. A couple of months later, which of the following terms would best describe the process seen in a femoral vein after recovery from her thrombophlebitis: A Acute inflammation B Rupture C Embolization D Organization E Propagation

(D) Thrombi may either lyse or will organize over time, with much of the clot eventually removed and the vascular lumen restored.

A 48-year-old man has had worsening severe headaches over the past 3 months. There are no abnormal findings on physical examination. Brain MR imaging shows a large 8 cm mass in the right posterior parietal region that extends across the splenium of the corpus callosum. A stereotaxic biopsy reveals an anaplastic astrocytoma. He is treated with radiation and chemotherapy. Two months later he experiences left upper quadrant abdominal pain, accompanied by hematuria. He then has an episode of sudden dyspnea and a chest CT scan shows large thromboemboli filling both main pulmonary arterial branches. Which of the following cardiovascular lesions is most likely to be found in this man? A Tear in the ascending aortic intima B Occlusive coronary atheromatous plaques C Hypertrophic cardiomyopathy D Epicardial metastases E Mitral marantic vegetations

(E) CORRECT. A He has both venous and arterial thromboembolic disease that suggests Trousseau syndrome. Non-bacterial thrombotic endocarditis (NBTE) is seen with this paraneoplastic condition. Though the small vegetations are bland, they often embolize, in this case in the systemic circulation to spleen and kidney. The highest rate of Trousseau syndrome occurs with high grade gliomas--about 25% of patients.

A 45-year-old man has had no major medical problems throughout his life, except for arthritis pain involving all extremities for the past 5 years. He has had worsening orthopnea and pedal edema in the past 6 months. There is no chest pain. On examination he is afebrile. A chest radiograph shows cardiomegaly with prominent left and right heart borders, along with pulmonary edema. Laboratory studies show serum sodium 139 mmol/L, potassium 4.3 mmol/L, chloride 99 mmol/L, CO2 25 mmol/L, urea nitrogen 18 mg/dL, creatinine 1.3 mg/dL, and glucose 167 mg/dL. Which of the following additional laboratory test findings is he most likely to have? A Spherocytes on his peripheral blood smear B Hemoglobin of 10.7 g/dL with MCV of 72 fL C Erythrocyte sedimentation rate of 79 mm/Hr D Anti-centromere antibody titer of 1:320 E Serum ferritin of 800 ng/mL

(E) CORRECT. He has findings of a cardiomyopathy with right and left heart failure. Hereditary hemochromatosis can produce iron deposition in visceral organs, including the heart. The serum ferritin is a good indicator of body iron stores. Hemochromatosis affects the pancreas as well, leading to diabetes mellitus. Deposition of iron in joints leads to arthritis. There is a gradual increase in body iron stores, so that the onset of disease is typically in the 40's in males and 60's in females.

Question 20 A 40-year-old man has a long history of chronic alcohol abuse. On physical examination his liver edge is firm on palpation of the abdomen, but liver span does not appear to be increased. An abdominal CT scan reveals a cirrhotic liver. He joins a support group for persons with chronic alcohol abuse and he stops drinking. Despite his continued abstinence from alcohol, he most likely remains at risk for development of which of the following diseases? A Hepatic adenoma B Focal nodular hyperplasia C Cholelithiasis D Angiosarcoma E Hepatocellular carcinoma F Non-Hodgkin lymphoma G Hemangioma

(E) CORRECT. Hepatocellular carcinoma occurs most often in the setting of cirrhosis (which is most often from chronic alcoholism and from chronic viral hepatitis B and C).

Question 44 A 60-year-old man has worsening dyspnea and swelling of his legs for the past month. On physical examination he has pitting edema to the hips as well as sacral edema. Diffuse rales are present in all lung fields. He is afebrile and normotensive. A chest radiograph shows a markedly enlarged heart along with pulmonary edema and bilateral pleural effusions. He develops abdominal pain in the last two days of life. At autopsy he is found to have patchy mucosal erythema involving 200 cm of small intestine. Which of the following conditions is most likely to produce this finding in his bowel? A Adenocarcinoma B Venous thrombosis C Volvulus D Incarcerated hernia E Ischemia

(E) CORRECT. Hypotension with ischemia is probably the most common cause for ischemic enteritis and/or colitis. This man's heart disease (probably a dilated form of cardiomyopathy with both right and left-sided congestive heart failure) led to reduced cardiac output with reduced tissue perfusion. Though the bowel has a rich anastomosing blood supply, when flow is reduced in all branches, then ischemic can occur.

A 43-year-old woman has noted increasing dyspnea for the past 6 years. On examination she is afebrile. Rales are auscultated in both lungs. A chest radiograph shows an enlarged cardiac silhouette and bilateral pulmonary edema. Past history reveals that, as a child she suffered recurrent bouts of pharyngitis with group A beta hemolytic streptococcal infections. Which of the following cardiac valves are most likely to be abnormal in this woman? A Aortic and tricuspid B Mitral and pulmonic C Aortic and pulmonic D Tricuspid and pulmonic E Mitral and aortic

(E) CORRECT. She has chronic rheumatic valvulitis with scarring associated with rheumatic heart disease. Her findings suggest left-sided heart failure. If the tricuspid valve is involved, then the mitral and aortic are probably involved as well. The most common single valve involved is the mitral.

Question 39 A 43-year-old previously healthy woman has noted bouts of sharp upper abdominal pain along with nausea for 3 weeks. On physical examination she has tenderness to palpation of the right upper quadrant. She has scleral icterus. A liver biopsy is performed and on microscopic examination shows only intracanalicular cholestasis in the centrilobular regions, along with swollen liver cells and portal tract edema. There is no necrosis and no fibrosis. There is no increase in stainable iron. Which of the following is the most likely diagnosis? A Chronic passive congestion B Hepatitis B viral infection C Extrahepatic biliary atresia D Hepatic veno-occlusive disease E Choledocholithiasis

(E) CORRECT. The bile stasis results from blockage of the biliary tract drainage. The source of the calculi is likely the gallbladder. Though most gallstones remain in the gallbladder, some may escape and travel into the common bile duct (choledocholithiasis).

A 58-year-old man has had an enlarging abdomen for 5 months. He has experienced no abdominal or chest pain. On physical examination he has a non-tender abdomen with no masses palpable, but there is a fluid wave. An abdominal CT scan shows a large abdominal fluid collection with a small cirrhotic liver. A chest radiograph shows a globally enlarged heart. He has vital signs showing T 37.1°C, P 78/minute, RR 16/minute, and BP 115/75 mm Hg. Which of the following cardiovascular conditions is he most likely to have? A Severe occlusive coronary atherosclerosis B Lymphocytic myocarditis C Myocardial amyloid deposition D Nonbacterial thrombotic endocarditis E Dilated cardiomyopathy

(E) CORRECT. The cardiomyopathy of chronic alcohol abuse has a dilated appearance. The shrunken, cirrhotic liver suggests alcohol abuse as an etiology.

A 27-year-old G2 P1 woman has a screening ultrasound performed at 18 weeks gestation. The fetus is appropriate in size for 18 weeks. The fetal kidneys, liver, head, and extremities appear normal. However, the fetus has a heart with a membranous ventricular septal defect, overriding aorta, and marked pulmonic atresia. If the baby were to be liveborn, which of the following characteristics on physical examination would most likely result from these cardiac defects? A Systemic hypertension B Weak lower extremity pulses C Clubbing of digits D Telangiectasias E Cyanosis

(E) CORRECT. The features described are those of tetralogy of Fallot, which producces a right-to left shunt with cyanosis from mixing of right heart blood with left heart blood.

A 50-year-old man has noted increasing swelling of his lower legs along with shortness of breath for 5 months. On physical examination he is afebrile, but diffuse crackles are heard over the lung bases. His heart rate is 80/minute and regular, with no murmurs, rubs, or gallops, but there is a prominent widened split S2. A chest radiograph reveals an increased size to the right heart border, along with bilateral pleural effusions. Laboratory studies show a serum troponin I of <0.4 ng/mL. Which of the following conditions is he most likely to have? A Alcoholic cardiomyopathy B Viral myocarditis C Bicuspid aortic valve D Constrictive pericarditis E Pulmonary interstitial fibrosis

(E) CORRECT. The findings suggest a predominantly right-sided congestive heart failure, which would be characteristic for cor pulmonale. Pulmonary hypertension most often results from obstructive or restrictive lung diseases. The second heart sound (S2) is comprised of aortic valve closure (A2) happening first and pulmonic valve closure (P2) occurring second. Normally, these are nearly superimposed. Normally, P2 is soft and heard only in the 2nd intercostal space at the left parasternal border. Increased pulmonary arterial pressure will increase the split and the loudness of P2.

Question 33 A 60-year-old postmenopausal woman on estrogen therapy has noted worsening swelling of her feet during the past 5 months. She has had increasing dyspnea at night for the past 2 months. She also has chronic arthritis. Her skin has become more darkly pigmented in the last 2 years without sun exposure. On physical examination there is no joint deformity. She has 2+ pitting edema to her thighs. A chest radiograph shows bilateral pleural effusions. Laboratory findings include a serum glucose of 196 mg/dL, creatinine 1.7 mg/dL, ferritin 9079 ng/mL, AST 25 U/L, ALT 38 U/L, alkaline phosphatase 49 U/L, total bilirubin 1.2 mg/dL, total protein 5.9 g/dL, and albumin 3.3 g/dL. Which of the following therapeutic approaches is most appropriate for this patient? A Begin corticosteroid therapy B Stop estrogen therapy C Give interferon therapy D Control her diabetes mellitus E Start regular phlebotomy

(E) CORRECT. The markedly elevated serum ferritin suggests extensive iron overload with hereditary hemochromatosis, a condition in which excessive iron absorbtion results in progressive accumulation of iron stores, often over 20 g by her age, particularly affecting liver, heart, joints, skin, and pancreas. Siblings may also carry an HFE gene mutation, most often the homozygous C282Y mutation. Phlebotomy will remove 250 mg of iron per unit of blood.

A 78-year-old woman has had increasing dyspnea for the past 5 years. On examination her blood pressure is 130/85 mm Hg. Her BMI is 35. Rales are auscultated in both lungs. Her B-type natriuretic peptide, C-reative protein and LDL cholesterol are elevated. A chest x-ray shows infiltrates in all lung fields and an enlarged heart. Echocardiography shows decreased ejection fraction with segmental wall motion abnormalities. Which of the following forms of cardiomyopathy is she most likely to have? A Alcoholic B Arrhthmogenic C Hypertrophic D Infiltrative E Ischemic

(E) CORRECT. The risk factors of obesity, elevated CRP and cholesterol, and age point toward ischemic heart disease, which can sometimes globally affect the heart, in the manner of a cardiomyopathy. The focal wall motion abnormalities suggest areas of ischemia/infarction. Her elevated BNP is consistent with congestive heart failure, as are the pulmonary edema infiltrates.

Question 10 A 25-year-old man has noted cramping abdominal pain for the past week associated with fever and low-volume diarrhea. On physical examination, there is right lower quadrant tenderness. Bowel sounds are present. His stool is positive for occult blood. A colonoscopy reveals mucosal edema and ulceration in the ascending colon, but the transverse and descending portions of the colon are not affected. Laboratory studies show serum anti-Saccharomyces cerevisiae antibodies. Which of the following microscopic findings is most likely to be present in biopsies from his colon? A Crypt abscesses B Entameba histolytica organisms C Adenocarcinoma D Band-like mucosal fibrosis E Non-caseating granulomas F Necrotizing vasculitis

(E) CORRECT. This history is most typical for Crohn disease, which is a form of inflammatory bowel disease that tends to involve the bowel in a segmental pattern.

A 77-year-old man with decreasing mental function has developed increasing dyspnea for the past 3 years. On physical examination he has a diastolic murmur. A chest CT scan shows an enlarged heart and prominent aorta. He dies from complications of pneumonia. At autopsy, the thoracic aorta is aneurysmally dilated. A microscopic section of the aorta shows chronic inflammation and luminal narrowing of vasa vasora. There is disruption of the aortic medial elastic fibers. Which of the following conditions is most likely to cause these findings? A Hypercholesterolemia B Marfan syndrome C Polyarteritis nodosa D Takayasu arteritis E Tertiary syphilis F ANCA-associated vasculitis

(E) CORRECT. Treponema pallidum is the organism that causes syphilis. Tertiary syphilis may have neurologic, joint, and cardiovascular complications. The endaortitis of the vasa vasora affects the media of the aorta, leading to buckling of the intimal surface in a 'tree bark' pattern, and aneurysmal dilation, including the aortic root, causing aortic regurgitation. This happens decades following initial infection.

A 65-year-old man has had increasing lower leg swelling along with reduced exercise tolerance for the past 5 years. He has chest pain on exertion. He has not experienced dyspnea. He has had 4 transient ischemic attacks in the past year. He has experienced abdominal pain in the past 2 months. Vital signs show T 37°C, P 82/min, RR 16/min, and BP 130/85 mm Hg. He has pitting edema to the knees bilaterally. The lower extremities have palpable pulses, no tenderness, and no erythema. An abdominal CT scan shows dilation of the abdominal aorta to 5 cm, filled with mural thrombus. Other family members have had similar problems. Which of the following underlying conditions is the most likely risk factor for his findings? A Factor V Leiden mutation B Adenocarcinoma of the colon C Multiple blunt trauma D Vasculitis E Metabolic syndrome

(E) He has findings associated with atherosclerosis, including coronary and aortic disease at least, with congestive heart failure and evidence for an aortic aneurysm. Metabolic syndrome predisposes to atherosclerosis. Some patients may eventually develop overt diabetes mellitus type 2.

A 25-year-old previously healthy primigravida is in the first trimester of pregnancy. During two successive prenatal visits, she has fasting serum glucose levels of 127 and 131 mg/dL. Prior to this pregnancy, her fasting serum glucose was 80 mg/dL. A hemoglobin A1C level is 8.1% at the last visit, at 18 weeks gestation. She feels well and has no major health problems. Which of the following problems is most likely to become apparent in the latter part of her pregnancy? A Intrauterine fetal growth retardation B Ketoacidosis C Hyperosmolar coma D Congenital anomalies E Placental insufficiency

(E) The big problem in gestational diabetes is eventual placental malfunction in later pregnancy (third trimester) with potential fetal demise.

A atudy of persons with essential hypertension is performed. They have blood pressures in the range of 140/90 to 160/100 mm Hg. Laboratory studies show normal serum electrolyte values. Which of the following physiologic abnormalities is most likely to account for their hypertension? A Hyperreninemia B Hyperaldosteronism C Decreased natriuretic peptide D Decreased angiotensin converting enzyem E Sodium retention F Catecholamine excess

(E) The causes for essential hypertension are obscure. The 'set point' for sodium diuresis is probably increased at a higher blood pressure in affected persons. Diuretics that promotes natriuresis are effective in treating essential hypertension.

Question 34 A 54-year-old Asian man has had malaise with a 6 kg weight loss over the past 7 months. On physical examination he has a firm, nodular liver edge. His stool is negative for occult blood. Laboratory studies show a positive serology for hepatitis B surface antigen, but negative serologies for hepatitis B surface antibody, hepatitis A IgM antibody, and hepatitis C antibody. His serum alpha-fetoprotein is 109 ng/mL. Which of the following neoplasms is he most likely to have? A Hemangioma B Hepatic adenoma C Hepatic angiosarcoma D Bile duct adenocarcinoma E Cholangiocarcinoma F Hepatocellular carcinoma G Non-Hodgkin lymphoma

(F) CORRECT. Chronic hepatitis and both micro- and macronodular cirrhosis carry an increased risk for liver cancer. Most often this is hepatocellular carcinoma. Either chronic hepatitis B or C infection increases the risk for primary liver cancer. An elevated AFP is characteristic for hepatocellular carcinoma.

Question 23 A 23-year-old primigravida gives birth at term following an uncomplicated pregnancy to a male infant with no apparent congenital anomalies. At 4 weeks of age the infant begins to exhibit forceful vomiting after each feeding. The infant had been fine previously and gaining weight normally. Which of the following conditions is the probable cause for his vomiting? A Congenital duodenal atresia B Necrotizing enterocolitis C Mallory-Weiss syndrome D Hirschsprung disease E Tracheo-esophageal fistula F Pyloric stenosis

(F) CORRECT. The male sex, age, and symptoms are all quite typical for pyloric stenosis, a condition that exhibits the genetic feature called the 'threshold of liability' in which males are more likely to have the disease (lower threshold) if born into a family with girls affected (higher threshold, and thus, more genetic tendencies for the disease to pass on).

Question 40 A first year medical student fails to use proper disinfection techniques in carrying out his microbiology experiment. Two weeks later, he has spiking fevers and cramping abdominal pain with diarrhea. On physical examination his temperature is 38.3 C, pulse 100/minute, respiratory rate 19/minute, and blood pressure 100/60 mm Hg. He has a palpable spleen tip and diffuse abdominal pain without masses. Laboratory studies show a WBC count of 2330/microliter, Hgb 13.8 g/dL, and platelet count 282,000/microliter. Which of the following organisms was he most likely using in his experiment? A Aspergillus niger B Entameba histolytica C Shigella flexneri D Clostridium difficile E Yersinia enterocolitica F Staphylococcus aureus G Rotavirus H Salmonella typhi

(H) CORRECT. He developed typhoid fever. Even though this is an acute bacterial infection, mononuclear inflammation and leukopenia are typical findings.

A 47-year-old man has lost 6 kg in 5 months. He has had a cough with hemoptysis along with pleuritic chest pain for the past 2 weeks. On physical examination his temperature is 37.5°C. A chest x-ray reveals a bilateral and predominantly upper lobe reticulonodular pattern of infiltrates with cavitation. A sputum sample is obtained and on light microscopic examination shows epithelioid cells with necrotic debris. Laboratory studies show a WBC count of 5890/microliter with 78% granulocytes, 15% lymphocytes, and 7% monocytes. Which of the following additional histologic findings is most likely to be present in his sputum?

Acid fast bacilli. The hemoptysis suggests that the granulomas have eroded enough parenchyma and involved a bronchus. A granulomatous reaction is typical for Mycobacterium tuberculosis infection

A 44-year-old woman, a non-smoker, has had a fever and cough for the past 4 days. She does not have hemoptysis. She has not experienced weight loss, malaise, nausea, or vomiting. On physical examination her temperature is 37.6°C. There are decreased breath sounds over the right upper lung. A chest radiograph reveals a 6 cm area of infiltrates in the right upper lobe. She is given a course of antibiotic therapy, but her cough persists. A month later her chest x-ray now reveals a 3 cm peripheral mass in the right upper lobe. Which of the following neoplasms is most likely to be present in this woman?

Adenocarcinoma. Peripheral lung cancers (adenocarcinoma and large cell carcinoma) show less of an association with smoking than central lung cancers (small cell and squamous cell carcinoma). The focal obstruction from the mass predisposed to infection.

A 61-year-old man has had a cough without production of much sputum for the past week. On physical examination he is afebrile. There are decreased breath sounds at the right lung base. A chest x-ray reveals an area of consolidation in the right lower lobe. He is given antibiotic therapy, but a month later the radiographic picture has not changed, and his cough continues. A bronchoalveolar lavage is performed and yields atypical cells along with scattered alveolar macrophages. Which of the following is the most likely diagnosis?

Adenoccarcinoma-in-situ. Adenocarcinoma-in-situ can spread in a pneumonia-like pattern. The lack of a change over time and the absence of a response to antibiotics should suggest an underlying non-infectious process. Adenocarcinomas may occur in non-smokers.

A 43-year-old woman who does not smoke becomes increasingly dyspneic over 8 years' time. She does not have a cough or increased sputum production. She is afebrile. On physical examination she has decreased breath sounds with hyperresonance in all lung fields. A chest radiograph reveals increased lucency of all lung fields. Laboratory studies show her serum alpha-1-antitrypsin level is 18 mg/dL. Which of the following microscopic portions of the lung is most likely to be affected by her condition?

Alveolar duct. Alpha-1-antitrypsin (AAT) deficiency leads to a panacinar form of emphysema which involves the distal acinus beyond the respiratory bronchiole.

A 41-year-old previously healthy woman, a non-smoker, has had episodes of fever, non-productive cough, and dyspnea over the past 3 months. Her symptoms disappeared after a month's vacation, but reappeared when she returned home to take care of her canaries. On physical examination there are no abnormal findings. A chest radiograph shows fine diffuse and nodular infiltrates in all lung fields. Her disease is most likely to be produced via which of the following inflammatory mechanisms?

Antigen-antibody complex formation. Birds make a lot of organic dust from their feathers. The result upon inhalation of the bird dust is an extrinsic allergic alveolitis. Getting away from the antigen (such as a vacation) will improve the situation. This is a form of type 3 hypersensitivity. It may progress to involve type 4 hypersensitivity if chronic.

A 66-year-old man has had increasing dyspnea for the past year. He is retired from the construction business. There are some rales auscultated in both lungs on physical examination. A chest radiograph reveals bilateral diaphragmatic pleural plaques with focal calcification as well as diffuse interstitial lung disease. A sputum cytology shows no atypical cells, only ferruginous bodies. Pulmonary function studies reveal a low FVC and a normal FEV1/FVC ratio. These findings are most likely to suggest prior exposure to which of the following environmental agents?

Asbestos crystals. These findings are classic for exposure to asbestos. Pleural plaques are more frequent in this condition than in other pneumonconioses, particularly with calcification. Asbestosis is a rare form of pneumoconiosis that can lead to restrictive lung disease. The ferruginous bodies are asbestos fibers encrusted with iron. Building materials from older houses may contain asbestos, which was used for years because of its fire retardant properties.

A 53-year-old man has had increasing dyspnea for the past 6 years, but no cough. On physical examination there is increased jugular venous distension. He is afebrile. A chest radiograph shows increased lucency in upper lung fields and increased lung volumes, with flattening of the diaphragmatic leaves. There are no infiltrates. The pulmonary arteries are enlarged and prominent bilaterally, and his right heart border is enlarged. Which of the following pathologic findings is most likely to be present in his main pulmonary arteries?

Atherosclerosis. Cor pulmonale is the result of pulmonary hypertension, which is the major cause for pulmonary atherosclerosis. His emphysema has reduced the pulmonary vascular bed, promoting the hypertension. Note that the forces driving systemic atherosclerosis are not operative on the pulmonary arterial system.

A 12-year-old girl has the acute onset of dyspnea and wheezing. She coughs up a large, thick mucus plug. She has experienced similar previous episodes for the past 4 years, all of which lasted 1 to 4 hours. On physical examination her vital signs include T 37.1°C, P 109/minute, RR 40/minute, and BP 90/60 mm Hg. There are decreased breath sounds in all lung fields. A chest radiograph reveals hyperinflation but no infiltrates. Laboratory studies show WBC count of 8300/microliter with differential count of 60 segs, 3 bands, 16 lymphs, 10 monos, and 11 eosinophils. A sputum sample examined microscopically has increased numbers of eosinophils. Which of the following is the most likely diagnosis?

Bronchial asthma. In an acute asthmatic episode, there can be an outpouring of mucus which, along with some dehydration, can lead to the formation of mucus plugs. These atopic asthmatic episodes in children are usually initiated by a type I hypersensitivity reaction, typically with exposure to an allergen such as pollen from goldenrod or other flowering plant. Up to 10% of children may be affected to some degree by atopy.

An 8-year-old boy at birth appeared to be a normal term baby, but his neontal course was complicated by the development of meconium ileus. His sweat chloride and immunoreactive trypsinogen are both found to be elevated. Throughout childhood he has experienced multiple increasingly severe bouts of pneumonia with a productive cough, often with Pseudomonas aeruginosa, and later Burkholderia cepacea, cultured from sputum. He is at greatest risk for development of which of the following pulmonary abnormalities?

Bronchiectasis. The chronic lung disease of cystic fibrosis often includes bronchiectasis, a disease characterized by inflammation with obstruction and dilation and destruction of bronchi. This process is diffuse throughout the lungs. The loss of pulmonary vascular bed with progressive bronchiectasis can lead to pulmonary hypertension and cor pulmonale. The sweat chloride is a good screening test, and can be applied as well as immunoreactive trypsinogen, to select for additional genomic testing, but testing is confounded by hundreds of possible CFTR gene mutations.

A male infant has initial Apgar scores of 5 and 6 at 1 and 5 minutes following birth by normal vaginal delivery at 30 weeks gestation. However, increasing respiratory distress in the next hour requires intubation and positive pressure ventilation. Two months later, the infant is finally taken off the ventilator, but still does not oxygenate normally. Which of the following diseases has this infant most likely developed?

Bronchopulmonary dysplasia. The bronchopulmonary dysplasia (BPD) is a complication of the treatment for neonatal respiratory distress. The positive pressure ventilation with the higher FIO2's, and the prolonged intubation, all contribute. Generally, these are premature infants who had a respiratory complication following birth, such as hyaline membrane disease.

A 64-year-old man has a 90 pack year history of smoking. For the past 5 years, he has had a cough productive of copious amounts of mucoid sputum for over 3 months at a time. He has had episodes of pneumonia with Streptococcus pneumoniae and Klebsiella pneumoniae cultured. His last episode of pneumonia is complicated by septicemia and brain abscess and he dies. At autopsy, his bronchi microscopically demonstrate mucus gland hypertrophy. Which of the following conditions is most likely to explain his clinical course?

Chronic bronchitis. Chronic bronchitis is defined clinically as persistent cough with sputum production for at least 3 months in at least 2 consecutive years. Air pollution and smoking are key causes for chronic bronchitis. The alteration of lung parenchyma predisposes to superimposed infection, typically with bacterial organisms.

A 25-year-old man receives a hematopoietic stem cell transplant for treatment of acute myelogenous leukemia. He develops increasing dyspnea 3 weeks later, along with fever and cough. On physical examination his temperature is 37.8°C. A chest radiograph shows irregular interstitial infiltrates. A bronchoalveolar lavage is performed an on cytologic examination shows cells that are enlarged and have prominent intranuclear inclusions. He is most likely to have an infection with which of the following organisms?

Cytomegalovirus. CMV produces a cytopathic effect with enlarged cells having prominent intranuclear inclusions. CMV infection occurs most often with immune compromise, as in this case folowing transplantation before engraftement.

A 43-year-old woman has had increasing dyspnea for 8 years. She has no cough or increased sputum production. On physical examination there is bilateral hyperresonance to percussion in all lung fields. A chest x-ray reveals increased lung volumes with flattening of the diaphragmatic leaves bilaterally. The right heart border is prominent. A chest CT scan demonstrates decreased attenuation in all lung fields, particularly lower lobes. Which of the following laboratory findings is she most likely to have?

Decreased serum alpha-1-antitrypsin. AAT deficiency leads to lack of an anti-protease, which leads to development of emphysema, typically a panlobular type affecting lower lobes more severely, and by the 5th decade.

A 60-year-old woman develops multiple organ failure 3 weeks following a pneumonia complicated by septicemia. Antibiotic therapy has resulted in sputum and blood cultures that are now without growth of organisms. Nevertheless, she requires intubation with mechanical ventilation, but it becomes progressively more difficult to maintain her oxygen saturations. Ventilatory pressures must be increased. A portable chest radiograph shows increasing opacification of all lung fields. Which of the following pathologic processes is most likely now to be present in her lungs?

Diffuse alveolar damage. Diffuse alveolar damage (DAD) is the pathologic term for adult respiratory distress syndrome (ARDS) that is the final common pathway for many acute lung injuries. DAD produces increasing interstitial thickening with mixed inflammation and features of an acute restrictive lung disease.

Following a vehicular accident with blood loss leading to prolonged, severe hypotension, a 30-year-old man is intubated and placed on a mechanical ventilator. He has progressively decreasing oxygen saturations despite increasing PEEP and FIO2 content of 100%. He remains afebrile. He dies 3 days later. At autopsy, the distal lungs show pink hyaline membranes, thickened interstitium, and many macrophages but few neutrophils. Which of the following pulmonary diseases most likely complicated his course?

Diffuse alveolar damage. Diffuse alveolar damage (or ARDS as it is known clinically) is the final event following severe lung injury from a variety of serious illnesses or accidents. In this case, it was probably initiated by the hypotension ('shock lung') and potentiated by the 100% oxygen generating free radical damage.

A 20-year-old man falls to the ground while jogging. He suffers a minor abrasion to his left hand. However, within minutes he becomes dyspneic with right-sided chest pain. Bystanders call an ambulance. On arrival at the hospital, he has tachypnea and tachycardia. On physical examination breath sounds are absent over the right lung fields. A chest radiograph shows that the mediastinum is shifted to the left, and there are no fractures. A thoracentesis on the right yields a rush of air. Which of the following conditions is he most likely to have?

Distal acinar emphysema. Distal acinar (paraseptal) emphysema is not common, but does account for a significant number of cases of spontaneous pneumothorax in young persons. It is not related to smoking. There are subpleural bullae that can burst, even with minimal trauma. They may be multiple, accounting for recurrent episodes. However, the total amount of lung involved is minimal, so pulmonary function tests will be normal between episodes. He developed a tension pneumothorax in this case.

Question 21 A 22-year-old woman has had progressive malaise for the past year. She has become increasingly obtunded over the past week. On physical examination she is afebrile. Laboratory studies show a plasma ammonia of 55 micromol/L along with serum total bilirubin of 5.8 mg/dL, direct bilirubin 4.6 mg/dL, AST 110 U/L, and ALT 135 U/L. Her serum ceruloplasmin is 14 mg/dL. The antimitochondrial antibody test is negative. A liver biopsy is performed and microscopic examination reveals increased copper deposition. Which of the following ocular findings is most likely to be present in this woman? A Bilateral papilledema B Macular degeneration C Proliferative retinopathy D Crystalline lens cataract formation E Corneal Kayser-Fleischer rings F Canal of Schlemm occlusion

E) CORRECT. These rings can be seen with a slit lamp examination. They are characteristic for Wilson disease, an autosomal recessive disorder with muation in the ATP7B gene that encodes for a copper-transporting ATPase. Patients have decreased serum ceruloplasmin, the copper-carrying protein, and increased tissue deposition of copper, particularly in liver, eye, and basal ganglia of brain.

A 58-year-old man has been a smoker for 40 years. He has worsening orthopnea over the past year. On examination he has a body mass index of 35. He is afebrile. His blood pressure is 165/110 mm Hg. Auscultation of his chest reveals rales in lower lung fields bilaterally. A chest x-ray shows bilateral lower lobe infiltrates and a prominent left heart border. Laboratory studies show his Hgb A1C is 10%. Which of the following pulmonary problems is he most likely to have?

Edema. He has multiple risk factors for ischemic heart disease leading to left heart failure and pulmonary edema.

A 6-year-old child has the sudden onset of dyspnea with wheezing. On physical examination he is afebrile but has absent breath sounds on the right. His temperature is 37°C, pulse 82/minute, respiratory rate 32/minute, and blood pressure 100/60 mm Hg. An arterial blood gas measurement shows pO2 95 mm Hg, pCO2 25 mm Hg, and pH 7.55. Following administration of 100% FiO2 by nasal canula, a repeat measurement shows pO2 95 mm Hg, pCO2 25 mm Hg, and pH 7.55. Which of the following is the most likely diagnosis?

Foreign body aspiration. An inhaled object could obstruct a bronchus completely, with air resorbtion and collapse of lung distal to the point of obstruction. This produces a shunt defect with a V/Q mismatch. Since there is perfusion but no ventilation, even 100% oxygen will not make a difference. His hyperventilation has acutely produced an uncompensated respiratory alkalosis.

A newborn male infant develops increasing respiratory distress within an hour following an uncomplicated vaginal delivery at 36 weeks gestation. A plain film radiograph reveals near opacification of both lungs. Despite intubation and positive pressure ventilation, the baby dies within two days. At autopsy, the infant's lungs demonstrate extensive pink hyaline membranes. Which of the following maternal conditions is most likely to increase the risk for this infant's respiratory distress?

Gestational diabetes. The hyperinsulinism in the baby as a result of the high maternal glucose impedes development of the type II pneumonocytes. By 36 weeks there should normally be sufficient surfactant to prevent hyaline membrane disease. Tests for fetal lung maturity include lamellar body count on amniotic fluid, fluorescence polarization (fpol), phosphatidyl glycerol (PG), and L/S ratio.

A 51-year-old man complains of a slight cough he has had for a week. He is a non-smoker. On auscultation of the chest his lung fields are clear. A chest radiograph shows a subpleural 'coin lesion' 2 cm in diameter in the right upper lobe. Which of the following is the most likely diagnosis for this lesion?

Granuloma. The differential diagnosis of a solitary peripheral coin lesion most often includes lung cancer (adenocarcinoma most likely), granuloma, or hamartoma. Many people have had a remote, subclinical tubercular or fungal infection leaving only a solitary granuloma. In this case the cough suggests possible active infection, but it may just be an incidental, unrelated finding.

Following an acute pharyngitis lasting 4 days, a 10-year-old boy develops neck pain and marked halitosis. On physical examination is breath is very malodorous. A CT scan shows an abscess in the peritonsillar region. Laboratory studies include a culture of the abscess which grows anaerobic flora. Which of the following aerobic organisms is most likely to be cultured from his abscess?

Group A Streptococcus. A peritonsillar abscess is usually a complication of a 'strep' throat in a child.

A previously healthy 5-year-old girl develops a fever along with dyspnea. On physical examination her temperature is 37.9°C. Her lung fields are clear to auscultation but there are expiratory wheezes. A chest x-ray reveals clear lung fields. Laboratory studies show Hgb 13.6 g/dL, platelet count 183,600/microliter, and WBC count 14,480/microliter. Her dyspnea suddenly worsens, and emergent bronchoscopy reveals bronchi plugged by exudates. These findings are most consistent with infection by which of the following organisms?

Haemophilus influenzae. H. influenzae pneumonia can follow a descending laryngotracheobronchitis. The infection can cause airway obstruction from fibrin-rich exudates containing neutrophils, similar to pneumococcal pneumonia more common in adults. Pulmonary consolidation is usually bronchopneumonia and patchy but may involve the entire lung lobe. Vaccination is available for type b, but now non encapsulated and non-typeable forms are increasing in frequency.

A 23-year-old primigravida is found on prenatal testing to have an elevated hemoglobin A1C level. Her pregnancy is uncomplicated until the 33rd week of gestation, when she has the onset of premature labor and delivers a male infant 24 hours later. The infant initially has Apgar scores of 4 and 6 at 1 and 5 minutes, but within an hour is in severe respiratory distress and requires intubation with mechanical ventilation. Which of the following pharmacologic therapies administered to the mother prior to birth could have helped to prevent this infant's neonatal respiratory distress?

Hydrocortisone. She has diabetes, which inhibits fetal lung development. At 33 weeks, the baby's lungs may not make sufficient surfactant, though type II pneumomonocytes are present and increasing in number. Corticosteroids administered to the mother help to speed up type II pneumonocyte production of surfactant in the baby. At birth, exogenous surfactant can be given to the neonate. In addition, diabetes tends to impede fetal lung maturation.

A 66-year-old woman has had a worsening non-productive cough with malaise for the past week. Her temperature increases to 37.4°C. A chest radiograph reveals diffuse bilateral pulmonary interstitial infiltrates in all lung fields. A sputum gram stain reveals normal flora and few neutrophils. She recovers over the next two weeks without sequelae. Infection with which of the following organisms most likely caused her illness?

Influenza A virus. The typical appearance of a viral lung infection is interstitial inflammation. The inflammatory response is primarily T lymphocytes.

A 55-year-old man with a 50 pack year history of smoking cigarettes has recently experienced an episode of hemoptysis along with his usual cough. On physical examination he has no abnormal findings. A sputum for cytology on microscopic examination shows atypical cells with hyperchromatic nuclei and orange-pink cytoplasm. Labortory studies show a serum calcium of 11.3 mg/dL, with phosphorus 2.1 mg/dL. Which of the following chest radiographic findings is this man most likely to have?

Large hilar mass Both squamous cell and small cell carcinomas, most common in smokers, tend to be central in location. Squamous cell carcinomas of the lung are associated with hypercalcemia, though overall the small cell carcinomas are best known for paraneoplastic syndromes.

A 30-year-old woman is in the 28th week of an uncomplicated pregnancy when she experiences the sudden onset of severe abdominal pain, followed by vaginal bleeding, then the onset of labor. A girl infant is delivered on the way to the hospital. On arrival within an hour, the baby is in respiratory distress and requires intubation and mechanical ventilation. A day later, a chest radiograph shows opacification of both lungs. The baby's respiratory status does not improve. Which of the following histopathologic findings is most likely to be present in this baby's lungs?

Minimal alveolar saccular development. The baby has been born prematurely, with incomplete lung development, and the lack of sufficient alveolar development along with minimal pulmonary surfactant production leads to hyaline membrane disease with respiratory distress in the newborn.

During a cardiac arrest, a 58-year-old man, a non-smoker, receives cardiopulmonary resuscitative measures and is brought to the hospital, where he is intubated. During the intubation procedure he suffers aspiration of gastric contents. Over the next 10 days he develops a non-productive cough along with a fever to 37.9°C. A chest radiograph reveals a 4 cm diameter mass with an air-fluid level in the right lung. A sputum gram stain reveals mixed flora. Which of the following conditions is he most likely to have?

Lung abscess. A Lung abscesses can result from aspiration of oropharyngeal or nasopharyageal contents, where bacterial organisms as part of normal flora can be transported to the lungs. The straighter bronchus to the right lung is more likely to conduct aspirated material. With septicemia, multiple abscesses are more likely to be present. The infection is often polymicrobial and difficult to treat.

A 65-year-old man has had no major medical problems prior to the past year, when he noted increasing malaise along with an 8 kg weight loss. He is a non-smoker. He currently does not have fever, cough, dyspnea, or any respiratory difficulties. On physical examination, he has non-tender supraclavicular lymphadenopathy. The lungs are clear to auscultation. A chest x-ray shows multiple solid nodules ranging from 1 to 3 cm scattered throughout all lung fields. No infiltrates or areas of consolidation are noted. Laboratory studies show Hgb 11.6 g/dL, Hct 34.7%, MCV 83 fL, and WBC count 6280/microliter. Which of the following pathologic processes in his lungs is most likely to account for these findings?

Metastatic carcinoma. Multiple persistent masses should suggest metastases, rather than a primary lung tumor. His lack of a cough or fever is against an infectious cause or aspiration.

A 41-year-old man with a 6 kg weight loss over the past 3 months now has had worsening fever, non-productive cough, and dyspnea for the past 3 days. His temperature is 38.2°C and there are diffuse rales in both lungs on auscultation. A chest radiograph shows patchy infiltrates in both lungs. Laboratory studies show WBC count 3250/microliter with 81 segs, 3 bands, 5 lymphs, and 11 monos. His CD4 lymphocyte count is 79/microliter. Cryptosporidium parvum organisms are found in a stool specimen. A bronchoalveolar lavage is performed, yielding fluid that microscopically demonstrates pink, foamy exudate with little inflammation. Which of the following additional findings on microscopic examination is he most likely to have in the BAL specimen?

Multiple cysts with GMS stain. He is most likely to have Pneumocystis jiroveci pneumonia in association with the acquired immunodeficiency syndrome (AIDS). Note his lymphopenia from the very low CD4 count. PCP infection produces an exudate composed of the Pneumocystis cysts and trophozoites with little accompanying inflammation. The clinical findings in this case are typical as well.

An 11-year-old girl has experienced dyspnea for the past 2 weeks. Her temperature is 37.3°C, pulse 85/minute, respiratory rate 30/minute, and blood pressure 110/60 mm Hg. On physical examination, her lung fields are clear to auscultation. Her heart rate is regular and no murmurs or gallops are heard. A chest radiograph shows prominent hilar lymphadenopathy along with a 1 cm peripheral right middle lobe nodule. No infiltrates are present. A sputum gram stain shows normal flora and routine bacterial culture reveals no pathogens. Which of the following conditions is she most likely to have?

Mycobacterium tuberculosis infection. This is a description of the typical 'Ghon complex' of an initial, or primary, TB infection. The peripheral granuloma does not produce symptoms, but the enlarged lymph nodes may impinge upon airways. Most persons with a primary infection, however, are asymptomatic and the infection goes unnoticed.

A 38-year-old previously healthy woman has had a worsening non-productive cough for the past 4 days. On physical examination her temperature is 38.3°C. A chest radiograph shows patchy infiltrates and diffuse interstitial markings. Laboratory studies show a sputum gram stain with mixed flora. Her Hgb is 12.9 g/dL, platelet count 229,450/microliter, and WBC count 5815/microliter. Her cold agglutinin titer is elevated. Following a course of erythromycin therapy, she improves, with no complications. Which of the following infectious agents is the most likely cause for her pulmonary disease?

Mycoplasma pneumoniae. Mycoplasma infection predominantly affects the interstitium, and is not a widespread alveolar filling process. It is a cause for a 'primary atypical pneumonia' which is difficult to diagnose because this organism is not cultured by routine methods for bacterial organisms. The cold agglutinin titer is elevated in about half of cases and is a characteristic finding. Many cases respond to antibiotic therapy with erythromycin.

A 63-year-old woman has had increasing dyspnea for 5 years. On physical examination her lungs are hyper-resonant without dullness. Tactile vocal fremitus is slightly decreased over all lung fields. Scattered expiratory wheezes and inspiratory rhonchi are present without basal crackles. She has a chest radiograph that reveals increased lung volumes and flattening of the diaphragmatic leaves. Spirometry demonstrates an FEV1 that is decreased more than the FVC so that the FEV1/FVC ratio is less than 70% of normal. Which of the following inhaled substances, which increases the elaboration of neutrophil elastase, is most likely to cause her pulmonary disease?

Nicotine. She has findings of emphysema, and smoking is the most likely underlying cause. The nicotine in the cigarette smoke is chemotactic for neutrophils, and cigarette smoke activates the alternative complement pathway, releasing more mediators for neutrophil recruitment. Neutrophil elastase can damage the lung parenchyma. Though neutrophils are not numerous in the lung with emphysema, the cumulative effect of even small numbers of neutrophils over many years leads to the tissue damage.

A 51-year-old man received an orthotopic cardiac transplant a month ago. He has developed a fever with cough over the past 5 days. On physical examination his temperature is 37.5°C. A chest CT scan shows consolidation with abscess formation involving the left lower lobe. A sputum gram stain reveals normal upper respiratory tract flora. He does not respond to antibiotic therapy over the next 6 months. His mental status deteriorates and MR imaging of the brain shows multiple abscesses. He is most likely to have an infection with which of the following organisms?

Nocardia braziliensis. Nocardia braziliensis infection can persist and lead to chronic abscesses. It can complicate the course of immunocompromised patients. Though the lung is the portal of entry, dissemination to brain is common.

A 41-year-old woman has a 1 year history of episodic dyspnea. On physical examination there are expiratory wheezes. Her chest radiograph shows a few small 0.5 cm perihilar nodules. Laboratory studies show an elevated serum IgE along with peripheral blood eosinophilia. A sputum sample shows eosinophils. Which of the following pathologic findings is most likely present in her bronchi?

Non-invasive aspergillosis. She has an allergic bronchopulmonary aspergillosis. Her asthma is exacerbated by a type I hypersensitivity reaction to the fungus in the bronchi.

A study is performed reviewing medical records of adults presenting with sudden onset of severe dyspnea. They were afebrile, with absent breath sounds over an entire lung, and chest x-ray showing pulmonary atelectasis of an entire lung. Which of the following conditions is most likely to produce these findings?

Penetrating chest trauma. Penetrating chest trauma would lead to pneumothorax with lung collapse (atelectasis).

A 54-year-old woman has had fever and dyspnea for a month along with a 2 kg weight loss. On physical examination her temperature is 37.7°C. A chest radiograph shows a reticulonodular pattern along with prominent hilar lymphadenopathy. A transbronchial lung biopsy is performed, and microscopic examination shows no viral inclusions, no fungi, no acid fast bacilli, and no atypical cells. Which of the following diseases is she most likely to have?

Sarcoidosis. The symptoms and signs are classic for granulomatous disease. Sarcoidosis often involves the hilar lymph nodes as well. No organisms can be found.

For the past 5 months, a 51-year-old woman has noted increased swelling of her lower legs as the day progresses. She has no fever and no cough. On physical examination, she has pitting edema to the knees. A chest radiograph reveals bilateral pleural effusions, and the right heart border is prominent. Laboratory studies show a serum AST of 238 U/L, ALT 263 U/L, LDH 710 U/L, and CK 127 U/L. Which of the following underlying diseases is most likely to cause these findings?

Recurrent thromboembolism. Pulmonary hypertension and subsequent right heart failure can occur in the small number of cases in which recurrent thromboembolism takes place. The right heart failure that occurs then leads to hepatic passive congestion with centrilobular necrosis that is the cause for the increased transaminases and LDH (but normal CK, since the heart is enlarged, but not ischemic).

A 50-year-old woman has lived in Oslo, Norway all her life and worked as a seamstress. She is a non-smoker, but she has had increasing shortness of breath, fever, weight loss, and night sweats for the past 4 months. On physical examination her temperature is 37.6°C. There are fine rales auscultated in all lung fields. A chest radiograph reveals hilar lymphadenopathy and a reticulonodular pattern of small densities in all lung fields. She demonstrates anergy by skin testing to mumps and Candida antigens. A transbronchial biopsy is performed that microscopically shows numerous small pulmonary interstitial non-caseating granulomas. Which of the following is the most likely diagnosis?

Sarcoidosis. Sarcoidosis is typified by non-caseating granulomas. However, culture of the tissue and a careful search histologically should be made for organisms before beginning therapy with corticosteroids. Extensive granulomatous disease can produce a restrictive pattern of pulmonary disease.

A 59-year-old man has been a cigarette smoker for the past 42 years. He has noted some blood-streaked sputum on coughing during the past week. He also has back pain. A chest radiograph shows a small 3 cm right hilar mass with several 1 to 2 cm peripheral lung nodules. A bone scan reveals multiple areas of increased uptake in the vertebrae, ribs, and pelvis. A sputum cytology reveals the presence of clusters of small cells having hyperchromatic nuclei and almost no cytoplasm. Which of the following laboratory test findings is he most likely to have as a consequence of his lung disease?

Serum sodium of 113 mmol/L. He has a small cell anaplastic carcinoma with widespread metastases. The syndrome of inappropriate ADH producing hyponatremia is one form of paraneoplastic syndrome seen with this particular carcinoma.

A 58-year-old man has developed a non-productive cough worsening over the past 2 months. Last week he noted the appearance of blood-streaked sputum. On physical examination there are some expiratory wheezes auscultated over the left lung. A chest radiograph reveals a 5 cm mass near the left lung hilum. A sputum cytology reveals the presence of small clusters of very hyperchromatic, pleomorphic cells with scant cytoplasm. Which of the following is the most likely predisposing factor to development of his pulmonary disease?

Smoking. Smoking remains the most frequent cause of lung cancer. Lung cancer does, however, occur in nonsmokers. A small cell anaplastic carcinoma, as in this patient, is virtually always seen in smokers. Small cell cancers arise in the central portion of the lung but are aggressive neoplasms that spread quickly.

At autopsy, a 60-year-old man is found to have a peripheral 7 cm area of golden-yellow consolidation on sectioning of the left lung. Microscopically, this area has alveoli filled with foamy macrophages. Which of the following conditions involving his lung is most likely to be responsible for this finding?

Squamous cell carcinoma. Most squamous cell carcinomas are located centrally and arise in bronchi, leading to obstruction of a large airway that can cause a distal lipid pneumonia. In this case, the breakdown of lung tissue distal to the mass yields an 'endogenous lipid pneumonia' with many macrophages. Some degree of atelectasis may also be present from air resorbtion distal to the obstruction.

A 40-year-old woman has had a high fever for a week, accompanied by a cough productive of yellowish sputum. On physical examination her temperature is 38.2°C. There are diffuse rales in all lung fields. Her chest radiograph reveals patchy infiltrates in all lung fields, and there is a 4 cm rounded area of consolidation in the left upper lobe that has an air-fluid level. Examination of her sputum reveals numerous neutrophils. Which of the following infectious agents is most likely causing her pulmonary disease?

Staphylococcus aureus. Pulmonary abscesses typically have an air-fluid level from liquefactive necrosis caused by the collection of neutrophils. More virulent bacterial organisms such as Staphylococcus aureus are likely to cause such a complication of a bronchopneumonia.

A 70-year-old woman at an extended care facility for the past two years has increasing inability to perform activities of daily living. She can no longer recognize family members. She is lethargic and spends most of her days in a wheelchair or in bed. She develops an acute febrile illness and is noted to be coughing up increasing quantities of yellowish sputum. Her temperature is 38°C. A chest x-ray shows infiltrates involving the left lower lobe. A sputum sample shows numerous neutrophils and gram-positive diplococci. Which of the following infectious agents is most likely to cause her pulmonary disease?

Streptococcus pneumoniae. She has a lobar pneumonia, which is most often a community aquired pneumonia (the nursing home counts as a community venue), following a debilitating course of Alzheimer disease. The most common organism is Streptococcus pneumoniae (pneumococcus).

A 70-year-old woman has been bedridden for 5 weeks following a cerebrovascular accident (CVA). She has the sudden onset of dyspnea, but has no further symptoms until two days later when she experiences left sided pleuritic chest pain. A radiologic imaging study show a wedge-shaped area consistent with hemorrhage based on the pleura of the left lower lobe. Which of the following pathologic findings in her pulmonary arterial branches is she most likely to have?

Thromboembolism. An embolus to a medium-sized arterial branch may not be large enough to kill the patient, but large enough to cause an infarction. Her bedridden state predisposes her to deep venous thrombosis and thromboembolism--the CVAs are due to separate systemic arterial problems--or the systemic and pulmonary embolization can be tied together by a hypercoagulable state, or more remotely by a 'paradoxical' embolus through a patent foramen ovale once the right sided-pressures increased following the initial pulmonary thromboembolic event.

On the 11th postoperative day following a radical prostatectomy for adenocarcinoma, a 70-year-old man is recovering uneventfully. He then ambulates to the bathroom, but upon returning to his bed he suddenly becomes extremely dyspneic and diaphoretic, with chest pain, palpitations, and a feeling of panic. Which of the following post-operative pulmonary complications has he most likely developed?

Thromboembolus. The activity of ambulation resulted in embolization of a thrombus that formed during his period of immobilization in leg or pelvic veins. The thrombus became an embolus and traveled up the vena cava, through the right heart, and to the pulmonary arterial tree of the lungs.